Lessee Leasing Arrangements Operating Leases Number of Renewal Number of terms which Company may exercise to renew lease Represents the number of the lessee's leasing arrangement renewal. Gross Unrealized Gains Available For Sale Debt Securities Gross Unrealized Gain Accumulated in Investments Amount of accumulated unrealized gain before deducting unrealized loss on investments in available-for-sale debt securities impacting investments. Investments and Cash Amortized Cost Total, Amortized Cost This item represents the cost of cash, cash equivalents, and debt securities, which are categorized neither as held-to-maturity nor trading, net of adjustments for other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any. Investments and Cash Fair Value Disclosure Sum of investments and unrestricted cash measured at fair value as of the balance sheet date. Total, Estimated Fair Value Total assets at fair value Share Based Compensation Arrangement by Share Based Payment Award Number of Shares Available for Grant Transferred Between Plans The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable. Shares reserved and transferred between plans Investment [Table] Business Combination Recognized Identifiable Assets Acquired and Liabilities Assumed Assets Held for Sale Assets held for sale The amount of assets held for sale (as defined) recognized as of the acquisition date. Nonemployee Officer [Member] Nonemployee officer and board member Represents information pertaining to the nonemployee officer of the entity. Milestones Minimum Annual Payment Milestone minimum annual payment Represents the amount of minimum annual payment for any years in which a milestone is not achieved under the agreement. Number of Shares of Common Stock to be Issued upon Meeting Various Future Milestones Number of shares of common stock to be issued upon meeting various future milestones Represents the number of shares of common stock that the entity is contractually obligated to issue upon meeting various future milestones. Debt Instrument, Accumulated Paid in Kind Interest Accumulated paid-in-kind interest Represents the amount of accumulated paid-in-kind interest. Amendment Description Stock Issued During Period, Shares, Stock Options Exercised Five Number of stock issued as a result of the fifth exercise of stock options. Exercise of employee stock options on September 24, 2012 (in shares) Amendment Flag Stock Issued During Period, Shares, Stock Options Exercised Four Number of stock issued as a result of the fourth exercise of stock options. Exercise of employee stock options on April 30, 2012 (in shares) Number of stock issued as a result of the first exercise of stock options. Exercise of employee stock options on June 30, 2009 (in shares) Stock Issued During Period, Shares, Stock Options Exercised One Stock Issued During Period, Shares, Stock Options Exercised Seven Number of stock issued as a result of the seventh exercise of stock options. Exercise of employee stock options on November 23, 2012 (in shares) Stock Issued During Period, Shares, Stock Options Exercised Six Number of stock issued as a result of the sixth exercise of stock options. Exercise of employee stock options on November 6, 2012 (in shares) Stock Issued During Period, Shares, Stock Options Exercised Three Number of stock issued as a result of the third exercise of stock options. Exercise of employee stock options on August 12, 2011 (in shares) Stock Issued During Period, Shares, Stock Options Exercised Two Number of stock issued as a result of the second exercise of stock options. Exercise of employee stock options on May 20, 2011 (in shares) Stock Issued During Period, Value, Stock Options Exercised Five Value of stock issued as a result of the fifth exercise of stock options. Exercise of employee stock options on September 24, 2012 Stock Issued During Period, Value, Stock Options Exercised Four Value of stock issued as a result of the fourth exercise of stock options. Exercise of employee stock options on April 30, 2012 Stock Issued During Period, Value, Stock Options Exercised One Value of stock issued as a result of the first exercise of stock options. Exercise of employee stock options on June 30, 2009 Stock Issued During Period, Value, Stock Options Exercised Seven Value of stock issued as a result of the seventh exercise of stock options. Exercise of employee stock options on November 23, 2012 Stock Issued During Period, Value, Stock Options Exercised Six Value of stock issued as a result of the sixth exercise of stock options. Exercise of employee stock options on November 6, 2012 Stock Issued During Period, Value, Stock Options Exercised Three Value of stock issued as a result of the third exercise of stock options. Exercise of employee stock options on August 12, 2011 Stock Issued During Period, Value, Stock Options Exercised Two Value of stock issued as a result of the second exercise of stock options. Exercise of employee stock options on May 20, 2011 Investment [Line Items] Cash equivalents and investments Temporary Equity, Issue Shares, Period Increase or Decrease Change in the number of shares of each type or class of stock classified as temporary equity during the period. Temporary Equity, Shares, Issued, Issuance Five The number of securities classified as temporary equity that have been sold (or granted) to the entity's shareholders in the fifth issuance during the period. Issuance of Series A preferred stock on January 28, 2011 (in shares) Temporary Equity, Shares, Issued, Issuance Four The number of securities classified as temporary equity that have been sold (or granted) to the entity's shareholders in the fourth issuance during the period. Issuance of Series A preferred stock on November 23, 2010 (in shares) Current Fiscal Year End Date Award Type [Axis] The number of securities classified as temporary equity that have been sold (or granted) to the entity's shareholders in the first issuance during the period. Issuance of Series A preferred stock on April 24, 2008 (in shares) Temporary Equity, Shares, Issued, Issuance One Temporary Equity, Shares, Issued, Issuance Three The number of securities classified as temporary equity that have been sold (or granted) to the entity's shareholders in the third issuance during the period. Issuance of Series A preferred stock on April 7, 2010 (in shares) Temporary Equity, Shares, Issued, Issuance Two The number of securities classified as temporary equity that have been sold (or granted) to the entity's shareholders in the second issuance during the period. Issuance of Series A preferred stock on January 27, 2010 (in shares) Temporary Equity, Value, Issued, Issuance Five The value of securities classified as temporary equity that have been sold (or granted) to the entity's shareholders in the fifth issuance during the period. Issuance of Series A preferred stock on January 28, 2011 The value of securities classified as temporary equity that have been sold (or granted) to the entity's shareholders in the fourth issuance during the period. Issuance of Series A preferred stock on November 23, 2010 Temporary Equity, Value, Issued, Issuance Four Temporary Equity, Value, Issued, Issuance One The value of securities classified as temporary equity that have been sold (or granted) to the entity's shareholders in the first issuance during the period. Issuance of Series A preferred stock on April 24, 2008 Temporary Equity, Value, Issued, Issuance Three The value of securities classified as temporary equity that have been sold (or granted) to the entity's shareholders in the third issuance during the period. Issuance of Series A preferred stock on April 7, 2010 The value of securities classified as temporary equity that have been sold (or granted) to the entity's shareholders in the second issuance during the period. Issuance of Series A preferred stock on January 27, 2010 Temporary Equity, Value, Issued, Issuance Two Accrued Franchise and Property Taxes Current Accrued franchise and property taxes Carrying value as of the balance sheet date of obligations incurred and payable for franchise and property taxes. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer). Grant price of stock awards expressed as percentage of the fair value of shares on the grant date as determined by various specified factors Represents the grant price of equity-based award expressed as percentage of the fair value of the shares on the grant date as determined by various specified factors. Share Based Compensation Arrangement by Share Based Payment Award Grant Price as Percentage of Fair Value of Shares on Grant Date as Determined by Various Specified Factors Debt conversion restriction period following the effective date of the Registration Statement Represents the period following the effective date of registration statement until which original debt cannot be converted in a noncash (or part noncash) transaction. Part noncash refers to that portion of the transaction not resulting in cash receipts or payments in the period. Debt Conversion Restriction Period Following Effective Date of Registration Statement Document Period End Date Gross Proceeds from Issuance of Convertible Preferred Stock Gross proceeds from sale of preferred stock The gross cash inflow from issuance of preferred stocks identified as being convertible into another form of financial instrument, typically the entity's common stock. Represents short term convertible notes, issued in January 2012. Short Term Convertible Notes Issued January 2012 [Member] Short term convertible notes issued January 2012 Short Term Convertible Notes Issued September and November 2012 [Member] Short term convertible notes issued September and November 2012 Represents short term convertible notes, issued in September and November 2012. Short term convertible notes issued September 2012 Represents short term convertible notes, issued in September 2012. September 2012 financing Short Term Convertible Notes Issued September 2012 [Member] November 2012 financing Short Term Convertible Notes Issued November 2012 [Member] Short term convertible notes issued November 2012 Represents the short term convertible notes issued in November 2012. Accrued Clinical Development Costs [Policy Text Block] Accrued Clinical Development Costs Disclosure of accounting policy for accrued clinical development costs. Warrants to Purchase Preferred Stock Disclosure of accounting policy for warrant liability. Warrant Liability Warrant Liability [Policy Text Block] In Process Research and Development [Abstract] In-Process Research and Development Series A1 Preferred Stock [Member] Outstanding nonredeemable series A-1 preferred stock or outstanding series A-1 preferred stock. Classified within stockholders' equity, if nonredeemable or redeemable solely at the option of the issuer. Classified within temporary equity, if redemption is outside the control of the issuer. Series A-1 preferred stock Series A 1 Convertible Preferred Stock Prepaid Clinical Development Costs, Current Represents the amount of consideration paid in advance for clinical development that provides economic benefits within a future period of one year or the normal operating cycle, if longer. Prepaid clinical development costs Other Prepaid Expense and Assets, Current Represents the amount of asset related to consideration paid in advance for other costs that provide economic benefits in future periods, and amount of other assets that are expected to be realized or consumed within one year or the normal operating cycle, if longer. Other prepaid and current assets Accrued Clinical Development Costs, Current Carrying value as of the balance sheet date of obligations incurred through that date and payable for clinical development. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle, if longer). Accrued clinical development costs Arrangements and Non-arrangement Transactions [Domain] Document and Entity Information Reverse Stock Split Reverse Stock Split [Abstract] Organization Consolidation and Presentation of Financial Statements [Table] Information pertaining to the organization and its principal activities. Fair Value Measurement Asset Transfers Between Levels Transfer of assets between levels Represents the transfer of assets between the levels of fair value hierarchy that have taken place during the period. Fair Value Measurement Liability Transfers Between Levels Transfer of liabilities between levels Represents the transfer of liabilities between the levels of fair value hierarchy that have taken place during the period. Incentive Stock Option and Restricted Stock Plan 2008 [Member] 2008 Incentive Stock Option and Restricted Stock Plan Represents information pertaining to 2008 Incentive Stock Option and Restricted Stock Plan. 2008 Plan Grant period of stock awards Represents the period from adoption of plan date that an equity-based award are granted. Share Based Compensation Arrangement by Share Based Payment Award Grant Period Share Based Compensation Arrangement by Share Based Payment Award, Award Vesting Period for Remaining Grant Amount Period for which remainder of grant amount will vest on the first day of each calendar quarter Represents the period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition for remaining grant amount. Share Based Compensation Arrangement by Share Based Payment Award Period from Cessation of Employment within which Options Expire if Not Exercised Period from cessation of employment within which options expire if not exercised Represents the period from cessation of employment within which options expire if not exercised. Share Based Compensation Arrangement by Share Based Payment Award Options Weighted Average Remaining Contractual Term [Abstract] Weighted-Average Remaining Contractual Term (Years) Share Based Compensation Arrangement by Share Based Payment Award Aggregate Intrinsic Value [Abstract] Aggregate Intrinsic Value Share Based Compensation Arrangement by Share Based Payment Award Options Vested and Expected to Vest and Exercisable [Abstract] Information about the stock option plan Assets Held For Sale Assets Held For Sale The entire disclosure for assets held-for-sale. Assets Held for Sale Disclosure [Text Block] Represents the amortization period of a promissory note. Notes Receivable Amortization Period Amortization period The entire disclosure for warrants. Warrants Disclosure [Text Block] Warrants Convertible Preferred Stock and Stockholders' Equity Convertible Preferred Stock and Stockholders Deficit Disclosure [Text Block] Convertible Preferred Stock and Stockholders' Equity Disclosure pertaining to the convertible preferred stock and stockholders' deficit. Schedule of Common Stock Reserved for Future Issuance [Table Text Block] Schedule of the number of common shares which could be issuable upon the conversion of convertible instruments or exercise of options Tabular disclosure of the number of common shares which could be issuable upon the conversion of convertible instruments or exercise of options. Number of New Series Preferred Stock Authorized Number of new series preferred stock authorized Represents the number of new series preferred stock authorized pursuant to amendment. Temporary Equity Percentage of Voting Power to be Held by Holders of Common and Preferred Stock for Determining Liquidation Preference Percentage of voting power required to be held by the holders of the common stock and preferred stock for determining liquidation preference Represents the percentage of voting power required to be held by the holders of the common stock and preferred stock for determining liquidation preference for temporary equity. Represents the percentage of preferred stock holders affirmative election required for automatic conversion of temporary equity. Percentage of Preferred Stockholders Affirmative Election Required for Automatic Conversion of Temporary Equity Percentage of preferred stock holders affirmative election required for automatic conversion of temporary equity Number of Times of Adjusted Original Issue Price of Preferred Stock Considered for Determining Automatic Conversion of Temporary Equity Number of times of adjusted original issue price of preferred stock considered for sale of common stock in a firmly under written public offering for determining automatic conversion of temporary equity Represents the number of times of adjusted original issue price of preferred stock considered for sale of common stock in a firmly under written public offering for automatic conversion of temporary equity. Gross Proceeds from Issuance Initial Public Offering Considered for Determining Automatic Conversion of Temporary Equity Gross proceeds from sale of entity's common stock in a firmly underwritten public offering considered for determining automatic conversion of temporary equity Represents the amount of gross proceeds (prior to deducting underwriting discounts and commissions) from sale of entity's common stock in a firmly underwritten public offering considered for determining automatic conversion of temporary equity. Conversion price (in dollars per share) The conversion price per share of the temporary equity to be converted to common stock. Temporary Equity Conversion Price Temporary Equity Conversion Rate Conversion rate Represents the conversion rate calculated as the original issue price of preferred stock divided by the preferred stock conversion price. Basis of Presentation and Significant Accounting Policies Organization Consolidation and Presentation of Financial Statements [Line Items] Short term borrowings with related parties, net of debt discount Reflects the total carrying amount as of the balance sheet date of related party debt, net of discounts, having initial terms less than one year or the normal operating cycle, if longer. Total short term convertible notes, net of debt discount Short Term Borrowings Related Party Net Amortization of Debt Discount Premium and Beneficial Conversion Amount of noncash expense included in interest expense to amortize debt discount (premium) and beneficial conversion costs associated with the related debt instruments. Excludes amortization of financing costs. Amortization of debt discount and beneficial conversion feature Amortization of debt discount and beneficial conversion Property and Equipment [Member] Property and equipment Represents activity related to property and equipment. Schedule of Debt Instruments [Table] A table or schedule providing information pertaining to short-term and long-term debt instruments or arrangements, including identification, terms, features, collateral requirements and other information necessary to a fair presentation. Series A Preferred Stock Warrant [Member] Warrants for preferred stock Warrant Represents a warrant to purchase Series A convertible preferred stock issued to purchasers of the reporting entity's convertible promissory notes. Series A preferred stock warrant Pfizer Promissory Note Pfizer Convertible Note [Member] Represents activity related to non-subordinated convertible note due to Pfizer. Pfizer note Pfizer Note Proceeds from warrant issuance The cash inflow from issuance of rights to purchase common shares calculated at estimated fair value using the Monte Carlo valuation model. Proceeds from Issuance of Warrants Fair Value Estimate Proceeds from issuance of preferred stock Proceeds from issuance of preferred stock, net of issuance costs Proceeds from Issuance of Preferred Stock and Preference Stock, Net of Issuance Costs Proceeds, net of issuance costs, from issuance of capital stock which provides for a specific dividend that is paid to the shareholders before any dividends to common stockholders and which takes precedence over common stockholders in the event of liquidation. Going Concern [Abstract] Going Concern License Agreement Reverse Stock Split Reverse Stock Split Disclosure [Text Block] Reverse Stock Split The entire disclosure for reverse stock splits. Represents the amount of proceeds required in a future equity financing for conversion of the unpaid principal and interest of the debt instrument. Proceeds from Equity Financing Required for Conversion of Debt Instrument Proceeds from equity financing required for conversion of the debt instrument Debt Instrument, Period of Common Stock Average Closing Price Considered for Conversion into Common Stock if Conversion made after Initial Public Offering Period of average closing price of common stock Represents the period of average closing price of entity's common stock considered for conversion of debt into common stock, if conversion is made after an initial public offering. Entity Well-known Seasoned Issuer Qualified Financing Occurs [Member] Qualified financing occurs Represents information pertaining to scenario when qualified financing occurs. Entity Voluntary Filers Qualified Financing Does Not Occur [Member] Qualified financing does not occur Represents information pertaining to scenario when qualified financing does not occur. Entity Current Reporting Status Represents exercisable value of warrants as a percentage of principal amount of the convertible promissory notes issued. Exercisable value of warrants as a percentage of principal amount of the convertible promissory notes issued Exercisable Value of Warrants as Percentage of Principal Amount of Convertible Promissory Notes Issued Entity Filer Category Class of Warrant or Right Term of Warrants Expiration term of warrants Represents the term of class of warrants or rights outstanding. Entity Public Float License Issue Fee License issue fee Represents activity related to issue fees incurred under terms of license agreements. Entity Registrant Name Payment due period following achievement of milestone Milestone Achievement Payment Period Represents the payment period for milestone payments once the milestone is achieved. Entity Central Index Key Represents information pertaining to lab equipment. Lab Equipment [Member] Lab equipment Short term convertible notes Short Term Borrowings Related Party Reflects the total carrying amount as of the balance sheet date of related party debt having initial terms less than one year or the normal operating cycle, if longer. Stock Option and Incentive Plan 2013 [Member] 2013 Stock Option and Incentive Plan Represents information pertaining to 2013 Stock Option and Incentive Plan. 2013 Plan Share Based Compensation Arrangement by Share Based Payment Award, Number of Additional Shares Authorized as Percentage of Shares Issued and Outstanding Percentage of increase in the number of shares reserved and available for issuance Represents the annual increase in number of shares of stock reserved and available for issuance under a share-based award plan by the specified percentage of the number of shares of stock issued and outstanding on the immediately preceding the end date. Entity Common Stock, Shares Outstanding Underwriter option Overallotment Option [Member] Represents activity related to underwriter overallotment options related to a public offering of equity. Over-allotment option Schedule of Condensed Balance Sheet and Equity Issuance Pro Forma Impact [Table Text Block] Schedule of impact of the Company's IPO on certain condensed balance sheet items on a pro forma basis Tabular disclosure of impact of an IPO on certain condensed balance sheet items on a pro forma basis. The amount of offering costs that were incurred during a noncash or partial noncash transaction. Deferred Offering Costs Incurred Initial public offering costs not yet paid Adjustments to Additional Paid in Capital Reclassification of Convertible Preferred Stock Warrant Liability Reclassification of convertible preferred stock warrant liability to additional paid-in capital Change in additional paid in capital (APIC) resulting from the reclassification of warrant liabilities related to temporary equity to additional paid-in capital. Initial Public Offering [Abstract] Initial Public Offering Warrant liabilities Primary financial statement caption encompassing warrant liabilities. Warrant Liability [Member] Additional Paid in Capital Line Item [Member] Additional paid-in capital Primary financial statement caption encompassing additional paid-in capital. Amount of accumulated unrealized loss before deducting unrealized gain on investments in available-for-sale debt securities impacting investments. Gross Unrealized Losses Available For Sale Debt Securities Gross Unrealized Loss Accumulated in Investments Share Based Compensation Arrangement by Share Based Payment Award Number of Additional Shares Authorized and Transferred Between Plans Shares reserved under previous plan and subsequently transferred to new plan Represents the number of remaining shares reserved under previous plan and transferred to a new plan during the period. Temporary Equity, Stock Issued During Period, Shares, New Issues Issuance of Series A preferred stock, net of issuance costs (in shares) Represents the stock number of shares classified as temporary equity issued during the period. Stock Issued During Period, Value, Exercise of Stock Options and Vesting of Restricted Stock Early exercise of stock options and vesting of restricted stock Value of stock issued as a result of the exercise of stock options and vesting of restricted stock. Entity Listing, Par Value Per Share Stock Issued During Period, Shares, Exercise of Stock Options and Vesting of Restricted Stock Early exercise of stock options and vesting of restricted stock (in shares) Number of share options (or share units) exercised and vested during the current period. Adjustments to Additional Paid in Capital Reclassification of Warrants from Liabilities to Equity Reclassification of warrants from liabilities to equity Represents the amount of increase in additional paid-in capital due to reclassification of warrants from liabilities to equity. Operating Lease Term Term period of lease Represents the term period of lease under the lease agreement. Operating Lease Period for Monthly Rent Increasing Operating lease period for monthly rent increasing in fixed monthly rent Represents the operating lease period for monthly rent increasing in fixed monthly rent under the lease agreement. Operating lease period after which monthly rent increase Represents the operating lease period after which the monthly rent increase every month. Operating Lease Period After which Monthly Rent Increase Every Month Assets in Progress [Member] Assets in Progress Represents information pertaining to assets in progress. Document Fiscal Year Focus Long Term Investments [Member] Long-term investments Represents investments that the entity has the intent to sell or dispose of for more than one year from the date of the balance sheet. Document Fiscal Period Focus Deferred Tax Assets Operating Loss Carryforwards Related to Stock Awards NOLs related to excess tax benefits Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards generated upon the settlement of stock awards. Designated Preferred Stock, Shares Authorized Designated preferred stock Represents the number of nonredeemable designated preferred shares. Reverse Stock Split Reverse Stock Split [Policy Text Block] Disclosure of accounting policy for reverse stock split. Initial Public Offering [Policy Text Block] Initial Public Offering Disclosure of accounting policy for initial public offering. Third Amendment to Operating Lease Agreement for Laboratory Facility in Plymouth Michigan [Member] Third amendment to the operating lease agreement for laboratory facility in Plymouth, Michigan Represents information pertaining to third amendment to the operating lease agreement for laboratory facility in Plymouth, Michigan. Operating Lease Adjusted Rentable Area Adjusted rentable laboratory space (in square feet) Represents the adjusted rentable area under the operating lease. Adjusted proportionate share of landlord's expenses and taxes (as a percent) Represents the percentage of adjusted proportionate share under the operating lease. Operating Lease Adjusted Proportionate Share Annual Base Rent under New Lease Agreement Annual base rent under new lease agreement Represents the annual base rent under new lease agreement Document Type Summary of Significant Accounting Policies Receivable Type [Axis] Accounts payable Accounts Payable, Current Amortization of premiums and discounts on investments Accretion (Amortization) of Discounts and Premiums, Investments Stock based compensation liability Accrued Employee Benefits, Current Accrued professional fees Accrued Professional Fees, Current Less accumulated depreciation and amortization Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment Accumulated other comprehensive income Accumulated Other Comprehensive Income (Loss), Net of Tax Accumulated Other Comprehensive Loss Accumulated Other Comprehensive Income (Loss) [Member] Accumulated Deficit during Development Stage [Member] Deficit Accumulated During the Development Stage Additional paid-in capital Additional Paid in Capital Additional Paid-in Capital [Member] Additional Paid-In Capital Adjustments to Additional Paid in Capital, Share-based Compensation, Requisite Service Period Recognition Stock-based compensation Adjustments, Noncash Items, to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract] Adjustments to reconcile net loss to net cash used in operating activities: Adjustments to Additional Paid in Capital, Convertible Debt with Conversion Feature Beneficial conversion feature from issuance of convertible notes Stock-based compensation expense Allocated Share-based Compensation Expense Expense recognized related to the vesting of stock options Amortization of debt issuance costs Amortization of Financing Costs Antidilutive Securities [Axis] Net Loss Per Common Share Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] Antidilutive Securities, Name [Domain] Total potential dilutive shares Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount Impairment of Long-Lived Assets Asset Impairment Charges [Abstract] Assets: Assets, Fair Value Disclosure [Abstract] Total assets Assets Current assets: Assets, Current [Abstract] Assets Assets [Abstract] Total current assets Assets, Current Fair value of assets held for sale Assets Held-for-sale, Long Lived, Fair Value Disclosure Total assets at fair value Assets, Fair Value Disclosure Assets held for sale Assets Held-for-sale, Current Investments, Estimated Fair Value Available-for-sale Securities, Debt Securities Available for sale securities Long-term investments, Estimated Fair Value Available-for-sale Securities, Debt Securities, Noncurrent Investments, Amortized Cost Available-for-sale Debt Securities, Amortized Cost Basis Total debt Borrowed Funds Balance Sheet Location [Axis] Balance Sheet Location [Domain] Basis of Presentation Basis of Presentation and Significant Accounting Policies [Text Block] Basis of Presentation Basis of Accounting, Policy [Policy Text Block] Pro Forma net loss per share applicable to common stockholders-diluted (unaudited) (in dollars per share) Business Acquisition, Pro Forma Earnings Per Share, Diluted Pro Forma net loss per share applicable to common stockholders-basic (unaudited) (in dollars per share) Business Acquisition, Pro Forma Earnings Per Share, Basic Cash Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Cash and Equivalents Intangible assets Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Indefinite-Lived Intangible Assets Stock Acquisition Business Acquisition [Line Items] Stock Acquisition Stock Acquisition Business Combination Disclosure [Text Block] Allocated total cost Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net [Abstract] Property and equipment Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment Finite-lived intangible assets Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles Total Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net Cash and Cash Equivalents [Axis] Cash and cash equivalents Cash and cash equivalents at beginning of period Cash and cash equivalents at end of period Cash and Cash Equivalents, at Carrying Value Cash and Cash Equivalents, Policy [Policy Text Block] Cash and Cash Equivalents Cash obtained in stock acquisition Cash Acquired from Acquisition Cash and Cash Equivalents, Fair Value Disclosure Cash equivalents, Estimated Fair Value Cash and cash equivalents at beginning of period Cash and cash equivalents at end of period Cash and cash equivalents, Carrying Value Cash, Cash Equivalents, and Short-term Investments Cash and cash equivalents Total Certificates of deposit Certificates of Deposit [Member] Number of shares of common stock to be purchased against outstanding warrants Class of Warrant or Right, Outstanding Capitalization information Class of Stock [Line Items] Class of Warrant or Right [Axis] Class of Warrant or Right [Domain] Warrants exercisable into common stock (in shares) Class of Warrant or Right, Number of Securities Called by Warrants or Rights Warrants exercisable into stock (in shares) Exercise price (in dollars per share) Class of Warrant or Right, Exercise Price of Warrants or Rights Warrants Class of Warrant or Right [Line Items] Class of Stock [Domain] Class of Warrant or Right [Table] Commitments and contingencies Commitments and contingencies (Note 5) Commitments and Contingencies. Commitments and contingencies Commitments and Contingencies Disclosure [Text Block] Common stock, par value (in dollars per share) Common Stock, Par or Stated Value Per Share Par value of common stock (in dollars per share) Issuance of common stock, on April 24, 2008, par value (in dollars per share) Issuance of common stock, par value (in dollars per share) Common Class A [Member] Common stock Common Stock [Member] Common Stock Common stock, $0.001 par value; 120,000,000 shares authorized as of March 31, 2014 and December 31, 2013; 15,394,226 shares issued and 15,379,311 outstanding at March 31, 2014 and 15,357,413 shares issued and 15,340,710 outstanding at December 31, 2013 Common Stock, Value, Issued Common stock Common stock, shares issued Balance (in shares) Balance (in shares) Common Stock, Shares, Issued Common stock, shares authorized Common Stock, Shares Authorized Number of shares of authorized common stock Common stock authorized pursuant to amended and restated certificate of incorporation filed (in shares) Number of additional shares of common stock authorized Common stock, shares outstanding Common Stock, Shares, Outstanding Employee Benefit Plan Components of deferred tax assets Components of Deferred Tax Assets [Abstract] Total comprehensive loss Comprehensive Income (Loss), Net of Tax, Attributable to Parent Computer equipment Computer Equipment [Member] Concentration Risk, Credit Risk, Policy [Policy Text Block] Concentration of Credit Risk Summary of future minimum payments Contractual Obligation, Fiscal Year Maturity Schedule [Table Text Block] Convertible Preferred Stock Convertible Preferred Stock [Member] Convertible preferred stock 10% Convertible promissory notes Convertible Notes Payable [Member] Convertible promissory note Long term debt Convertible Debt, Noncurrent Convertible debt Convertible Debt Securities [Member] Debt Debt Instrument [Line Items] Common stock issuable on conversion of debt (in shares) Debt Instrument, Convertible, Number of Equity Instruments Principal amount of the note converted Debt Conversion, Original Debt, Amount Issuance of preferred stock in exchange for convertible promissory notes, net of issuance costs (in shares) Debt Conversion, Converted Instrument, Shares Issued Conversion of convertible promissory notes into Series A preferred stock (in shares) Number of shares of preferred stock issued upon conversion of note (in shares) Aggregate principal amount Debt Instrument, Face Amount Outstanding principal Fair value of beneficial conversion feature Debt Instrument, Convertible, Beneficial Conversion Feature Debt Conversion Description [Axis] Debt Conversion of convertible promissory notes, including accrued interest of $923 into Series A preferred stock Debt Conversion, Converted Instrument, Amount Issuance of preferred stock in exchange for convertible promissory notes, net of issuance costs Outstanding principal amount Long-term Debt, Gross Aggregate balance Debt Debt Disclosure [Text Block] Debt Conversion, Name [Domain] Debt Instrument [Axis] Conversion price (in dollars per share) Debt Instrument, Convertible, Conversion Price Debt Instrument, Name [Domain] Discount on short term convertible notes Debt Instrument, Unamortized Discount Accrued interest during period Debt Instrument, Increase, Accrued Interest Interest rate (as a percent) Debt Instrument, Interest Rate, Stated Percentage Interest rate of promissory note (as a percent) Deferred offering costs Deferred Offering Costs Deferred tax assets: Deferred Tax Assets, Gross [Abstract] Deferred tax assets, before valuation allowance Deferred Tax Assets, Gross Total deferred tax assets Temporary differences Deferred Tax Assets, Other Net deferred tax assets Deferred Tax Assets, Net of Valuation Allowance Federal and state operating loss carryforwards Deferred Tax Assets, Operating Loss Carryforwards Valuation allowance Deferred Tax Assets, Valuation Allowance Contributions to the 401(k) Plan Defined Contribution Plan, Cost Recognized Depreciation expense Depreciation Deficit accumulated during the development stage Development Stage Enterprise, Deficit Accumulated During Development Stage Stock Compensation Disclosure of Compensation Related Costs, Share-based Payments [Text Block] Stock Compensation Dividends declared, accrued or paid Dividends, Preferred Stock Net loss per common share (basic and diluted) (in dollars per share) Earnings Per Share, Basic and Diluted Net Loss Per Common Share Earnings Per Share [Text Block] Net Loss Per Common Share Effective income tax rate Effective Income Tax Rate Reconciliation, Percent Reconciliation of the U.S. statutory income tax rate to the Company's effective tax rate Effective Income Tax Rate Reconciliation, Percent [Abstract] State income tax benefit, net of federal benefit Effective Income Tax Rate Reconciliation, State and Local Income Taxes, Percent Permanent items Effective Income Tax Rate Reconciliation, Nondeductible Expense, Percent Other Effective Income Tax Rate Reconciliation, Other Adjustments, Percent Change in valuation allowance Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation Allowance, Percent Federal income tax (benefit) at statutory rate Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent Accrued employee-related costs Employee-related Liabilities, Current Accrued compensation Common shares under option Employee Stock Option [Member] Total unrecognized compensation cost (in dollars) Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized Unrecognized compensation cost (in dollars) Weighted-average period over which remaining unrecognized compensation cost will be recognized Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition Equipment [Member] Equipment acquired, not intended for use Lab equipment Development Stage Entities, Equity 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and Liabilities Assumed [Table Text Block] Summary of the Company's capitalization upon closing of its initial public offering Schedule of Common Stock Outstanding Roll Forward [Table Text Block] Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block] Schedule of the Company's financial assets and liabilities that have been measured at fair value on a recurring basis Schedule of anti-dilutive securities excluded from the calculation of diluted net loss per share Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table Text Block] Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table] Schedule of activity under the Company's stock option plan Schedule of Share-based Compensation, Stock Options, Activity [Table Text Block] Summary of activity relating to the Company's options to purchase common stock Schedule of weighted-average assumptions used to compute the share-based 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