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Compensation Arrangement with Individual, Share-based Payments [Line Items] Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items] Deferred Federal Income Tax Expense (Benefit) Federal Deferred Foreign Income Tax Expense (Benefit) Foreign Deferred Income Tax Expense (Benefit) Total deferred income tax expense Deferred Rent Credit Deferred rent Deferred Rent Non Current Deferred Rent Non Current Long-term deferred rent and lease liability Deferred Revenue Deferred revenue related to research and development services Deferred Revenue Disclosure [Text Block] Revenue Recognition Deferred Revenue, Noncurrent Long-term deferred revenue Deferred Revenue, Period Increase (Decrease) Amortization of Kissei upfront payment Deferred State and Local Income Tax Expense (Benefit) State Deferred Tax Assets, Capitalized Expenses Deferred Tax Assets, Capitalized Expenses Capitalized licenses Deferred Tax Assets, Gross Total deferred tax assets Deferred Tax Assets, Net Net 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Purchase Plan Employee Stock Option [Member] Stock Option Employee Stock Purchase Plan, Number Of Shares Available for Issuance Employee Stock Purchase Plan, Number Of Shares Available for Issuance Shares available for future issuance Employee stock purchase plan offering period. 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Increase Decrease In Accounts Payable Accrued Expenses Income Taxes Payable And Deferred Rent Accounts payable, income tax payable, accrued expenses and deferred rent Increase (Decrease) in Employee Related Liabilities Accrued compensation and related expenses Increase (Decrease) in Operating Capital [Abstract] Changes in assets and liabilities: Increase (Decrease) in Prepaid Expense and Other Assets Prepaid expenses and other assets Increase (Decrease) in Receivables Receivables Increase In Ownership Percentage Increase In Ownership Percentage Increase of ownership of certain stockholders or public groups in the stock, percentage Carrying amount as of the balance sheet date, which is the fair value of the acquired in-process technology, adjusted for any amortization recognized after market feasibility has been achieved and for any impairment charges. 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Contingencies [Table] Loss Contingencies [Table] Macquarie Capital Incorporated [Member] Macquarie Capital Incorporated [Member] MCUSA Maximum [Member] Maximum Minimum [Member] Minimum Net Cash Provided by (Used in) Financing Activities, Continuing Operations Net cash provided by financing activities Net Cash Provided by (Used in) Financing Activities, Continuing Operations [Abstract] Financing activities: Net Cash Provided by (Used in) Investing Activities, Continuing Operations Net cash used in investing activities Net Cash Provided by (Used in) Investing Activities, Continuing Operations [Abstract] Investing activities: Net Cash Provided by (Used in) Operating Activities, Continuing Operations Net cash provided by (used in) operating activities Net Cash Provided by (Used in) Operating Activities, Continuing Operations [Abstract] Operating activities: Net Income (Loss) Attributable to Parent Net income (loss) Net loss Net Income (Loss) Available to Common Stockholders, Basic Net income (loss) applicable to common stockholders Net loss applicable to common shareholders Net loss applicable to common stockholders New Accounting Pronouncements, Policy [Policy Text Block] Recent Accounting Pronouncements Operating Expenses Total operating expenses Total operating expenses Operating Expenses [Abstract] Operating expenses: Operating Income (Loss) Operating loss Operating Leased Assets [Line Items] Operating Leased Assets [Line Items] Operating Leases, Future Minimum Payments Due Total minimum payments Operating Leases, Future Minimum Payments Due, Next Twelve Months 2015 Operating Leases, Future Minimum Payments, Due in Five Years 2019 Operating Leases, Future Minimum Payments, Due in Four Years 2018 Operating Leases, Future Minimum Payments, Due in Three Years 2017 Operating Leases, Future Minimum Payments, Due in Two Years 2016 Operating Leases of Lessee Disclosure [Table Text Block] Future Minimum Payments Operating Leases, Rent Expense, Minimum Rentals Rent expense Operating Loss Carryforwards Net operating loss carry-forwards Operating Loss Carryforwards, Expiration Year Operating Loss Carryforwards, Expiration Year Net operating loss carry forward, expiration year Option Indexed to Issuer's Equity, Type [Axis] Option Indexed to Issuer's Equity, Type [Axis] Option Indexed to Issuer's Equity, Type [Domain] Option Indexed to Issuer's Equity, Type [Domain] Organization, Consolidation and Presentation of Financial Statements [Abstract] Organization, Consolidation and Presentation of Financial Statements [Abstract] Organization, Consolidation, Basis of Presentation, Business Description and Accounting Policies [Text Block] Organization and Summary of Significant Accounting Policies Other Accrued Liabilities, Current Other Other Asset Amortization Period Other Asset Amortization Period Warrant, amortization period Other Commitment Future potential milestone payments Other Comprehensive Income (Loss), Foreign Currency Transaction and 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Under Espp Percentage of employee compensation for purchase of common stock under ESPP Postemployment Benefits [Abstract] Postemployment Benefits [Abstract] Preferred Stock [Member] Preferred stock Preferred Stock, Par or Stated Value Per Share Preferred stock, par value Preferred Stock, Shares Authorized Preferred stock, shares authorized Preferred Stock, Shares Issued Preferred stock, shares issued Preferred Stock, Shares Outstanding Preferred stock, shares outstanding Preferred Stock, Value, Issued Preferred stock, $0.01 par value; 3,000,000 shares authorized at December 31, 2014 and 2013; 220,000 shares issued and outstanding at December 31, 2014 and 2013 Prepaid Expense and Other Assets, Current Prepaid expense and other current assets Private Placement [Member] Private Placement Proceeds from Issuance of Common Stock Stock purchase agreement, proceeds Proceeds From Issuance Of Common Stock Gross Proceeds From Issuance Of Common Stock Gross Common Stock purchase agreement, gross proceeds from sale Stock purchase agreement, gross proceeds Proceeds From Issuance Of Common Stock Net Proceeds From Issuance Of Common Stock Net Common Stock purchase agreement, net proceeds from sale Stock purchase agreement, net proceeds Proceeds from Issuance of Private Placement Aggregate purchase price for shares and warrants under private placements Proceeds from Issuance of Private Placement Net Proceeds from Issuance of Private Placement Net Net Proceeds form issuance of shares and warrants in private placement Proceeds From Issuance Of Stock Proceeds From Issuance Of Stock Gross proceeds Proceeds from Issuance or Sale of Equity Proceeds from issuance of common stock and warrants, net of issuance costs Proceeds from Refunds from Suppliers of Material Payment received from vendor Proceeds from Sale of Property, Plant, and Equipment Proceeds from sales of property and equipment Proceeds from Stock Options Exercised Proceed from stock options exercised Proceeds from Warrant Exercises Proceeds from warrant exercises Warrants, exercisable value Proceeds Or Payments For Issuance Or Repurchase Of Common Stock Net Proceeds Or Payments For Issuance Or Repurchase Of Common Stock Net Net proceeds from issuance of Treasury Stock under ESPP Product Development [Member] Product Development [Member] Product Development Property, Plant and Equipment [Abstract] Property, Plant and Equipment [Abstract] Property, Plant, and Equipment Disclosure [Line Items] Property, Plant, and Equipment Disclosure [Line Items] Property, Plant, and Equipment Disclosure [Line Items] Property, Plant, and Equipment Disclosure [Table] Property, Plant, and Equipment Disclosure [Table] Property, Plant, and Equipment Disclosure [Table] Property, Plant and Equipment, Gross Property, Plant and Equipment, Gross, Total Property, Plant and Equipment, Net Property and equipment, net Property and equipment, net Property, Plant and Equipment [Table Text Block] Property and Equipment Net Quarterly Financial Data [Line Items] Quarterly Financial Data [Line Items] Quarterly Financial Data [Line Items] Quarterly Financial Information Disclosure [Abstract] Quarterly Financial Information Disclosure [Abstract] Quarterly Financial Information [Text Block] Quarterly Financial Data Range [Axis] Range [Axis] Range [Domain] Range [Domain] Receivables, Net, Current Receivable Reconciliation of Effective Income Tax Rate [Table] Reconciliation of Effective Income Tax Rate [Table] Reconciliation of Effective Income Tax Rate [Table] Related Party [Domain] Related Party [Domain] Related Party Transaction [Line Items] Related Party Transaction [Line Items] Related Party Transactions [Abstract] Related Party Transactions [Abstract] Related Party [Axis] Related Party [Axis] Related Party Transactions Disclosure [Text Block] Related Party Transactions Research and Development Arrangement, Contract to Perform for Others, Type [Axis] Research and Development Arrangement, Contract to Perform for Others, Type [Axis] Research and Development Arrangement, Contract to Perform for Others, Compensation Earned Revenue relating to research and development services Research and Development Arrangement, Contract to Perform for Others, Type [Domain] Research and Development Arrangement, Contract to Perform for Others, Type [Domain] Research and Development Credits, Expiration Year Research and Development Credits, Expiration Year Research and Development Credits, expiration period Research and Development Expense Research and development expense Research and development Research and Development Expense [Member] Research and development costs Research Development And Patents Expense Research Development And Patents Expense Research, development and patents Research Development and Patents Expense, [Policy Text Block] Research Development and Patents Expense, [Policy Text Block] Research, Development and Patents Retained Earnings (Accumulated Deficit) Accumulated deficit Retained Earnings [Member] Accumulated deficit Revenue Recognition [Abstract] Revenue Recognition [Abstract] Revenue Recognition, Policy [Policy Text Block] Revenue Recognition Policy Revenues Revenues Revenues [Abstract] Revenues: Sale Duration For Common Stock Under Purchase Agreement Sale Duration For Common Stock Under Purchase Agreement Stock purchase agreement, term of agreement Sale of Stock, Description of Transaction Stock Purchase Agreement, maximum amount of sale terms Sale of Stock, Name of Transaction [Domain] Sale of Stock, Name of Transaction [Domain] Sales Commission Sales Commission Sales commission as a percentage of gross proceeds Sales Revenue, Services, Net Research and development service revenue Scenario 5 [Member] Scenario 5 [Member] Scenario 5 Scenario 4 [Member] Scenario 4 [Member] Scenario 4 Scenario 1 [Member] Scenario 1 [Member] April 17, 2013 At Market Sales Agreement Scenario 3 [Member] Scenario 3 [Member] The second at-the-market equity distribution agreement Scenario 2 [Member] Scenario 2 [Member] October 16, 2013 At Market Sales Agreement Scenario, Unspecified [Domain] Scenario, Unspecified [Domain] Schedule of Accrued Liabilities [Table Text Block] Accrued Expenses Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table] Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table] Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table Text Block] Securities Excluded from Diluted Net Loss per Common Share Schedule of Capitalization, Equity [Table] Schedule of Capitalization, Equity [Table] Schedule of Components of Income Tax Expense (Benefit) [Table Text Block] Reconciliation of Income Tax Expense Schedule of Deferred Compensation Arrangement with Individual, Share-based Payments [Table] Schedule of Deferred Compensation Arrangement with Individual, Share-based Payments [Table] Schedule of Deferred Tax Assets and Liabilities [Line Items] Schedule of Deferred Tax Assets and Liabilities [Line Items] Schedule of Deferred Tax Assets and Liabilities [Line Items] Schedule of Deferred Tax Assets and Liabilities [Table] Schedule of Deferred Tax Assets and Liabilities [Table] Schedule of Deferred Tax Assets and Liabilities [Table] Schedule of Deferred Tax Assets and Liabilities [Table Text Block] Components of Deferred Income Taxes Schedule of Effective Income Tax Rate Reconciliation [Table Text Block] Reconciliation of Federal Statutory Income Tax Rate to Effective Income Tax Rate Schedule of Effective Tax Rate Reconciliation [Line Items] Schedule of Effective Tax Rate Reconciliation [Line Items] Schedule of Effective Tax Rate Reconciliation [Line Items] Schedule of Income before Income Tax, Domestic and Foreign [Table Text Block] Reconciliation of Income (Loss) before Income Taxes for Domestic and Foreign Locations Schedule of Operating Leased Assets [Table] Schedule of Operating Leased Assets [Table] Schedule Of Quarterly Financial Data [Table] Schedule Of Quarterly Financial Data [Table] Schedule Of Quarterly Financial Data [Table] Schedule of Quarterly Financial Information [Table Text Block] Summarized Quarterly Data Schedule of Related Party Transactions, by Related Party [Table] Schedule of Related Party Transactions, by Related Party [Table] Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Schedule of Share-based Compensation, Stock Options, Activity [Table Text Block] Summary of Stock Option Activity and Related Information Schedule of Share-based Payment Award, Employee Stock Purchase Plan, Valuation Assumptions [Table Text Block] Weighted-Average Assumptions for ESPP Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block] Weighted-Average Assumptions for Stock Option Schedule of Stockholders Equity [Table Text Block] Common Stock Reserved for Future Issuance Securities Purchase Agreement [Member] Securities Purchase Agreement [Member] Purchase Agreement Segment Reporting, Policy [Policy Text Block] Segment Reporting Selling, General and Administrative Expenses [Member] General and administrative expenses Series B Preferred Stock [Member] Series B Convertible Preferred Stock Share-based Compensation Non-cash stock-based compensation Stock-based compensation expense Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period Stock option, vesting period Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period Options granted expiration term Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions and Methodology [Abstract] Weighted-average assumptions for stock options and ESPP Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate Dividend yield Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term Expected option term (in years) Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate Expected volatility of common stock Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate Risk-free interest rate Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant Stock option available for future grant Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract] Weighted Average Contractual Life Share-based Compensation Arrangement by Share-based Payment Award, Options, Aggregate Intrinsic Value [Abstract] Share-based Compensation Arrangement by Share-based Payment Award, Options, Aggregate Intrinsic Value [Abstract] Aggregate Intrinsic Value Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value Aggregate Intrinsic Value, Exercisable at December 31, 2014 Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number Stock Options,Exercisable at December 31, 2014 Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Exercise Price Weighted Average Exercise Price,Exercisable at December 31, 2014 Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term Weighted Average Contractual Life, Exercisable at December 31, 2014 Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures and Expirations in Period Stock Options, Cancelled Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures and Expirations in Period, Weighted Average Exercise Price Weighted Average Exercise Price, Cancelled Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross Common stock options, granted Stock Options, Granted Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value Weighted-average fair value, per option Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value Aggregate Intrinsic Value, Ending balance Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number Stock Options, Ending Balance Stock Options, Beginning Balance Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward] Number of Option Shares Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price Weighted Average Exercise Price, Ending Balance Weighted Average Exercise Price, Beginning Balance Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract] Weighted Average Exercise Price Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term Weighted Average Contractual Life, Ending balance Equity Award [Domain] Equity Award [Domain] Share-based Compensation Arrangements by Share-based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price Weighted Average Exercise Price, Exercised Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price Weighted Average Exercise Price, Granted Share-based Compensation, Option and Incentive Plans Policy [Policy Text Block] Stock-Based Compensation Share purchase agreement. Share Purchase Agreement [Axis] Share Purchase Agreement [Axis] Share purchase agreement. Share Purchase Agreement [Domain] Share Purchase Agreement [Domain] Share purchase agreement. Share Purchase Agreement [Member] Kissei Stock Purchase Agreement Shares, Outstanding Ending Balance (in shares) Beginning Balance (in shares) Class of Stock [Axis] Class of Stock [Axis] Equity Components [Axis] Equity Components [Axis] Statement [Line Items] Statement [Line Items] Statement of Cash Flows [Abstract] Statement of Cash Flows [Abstract] Statement of Financial Position [Abstract] Statement of Financial Position [Abstract] Statement of Stockholders' Equity [Abstract] Statement of Stockholders' Equity [Abstract] Scenario [Axis] Scenario [Axis] Statement [Table] Statement [Table] Stock Compensation Plan [Member] 2004 Plan and 2013 Plan Stockholders' Equity Attributable to Parent Ending Balance Beginning Balance Total stockholders' equity Stockholders' Equity Attributable to Parent [Abstract] Stockholders' equity: Stockholders' Equity Note Disclosure [Text Block] Stockholders' Equity Stock Issuance Limit Under Employee Stock Purchase Plan Description Stock Issuance Limit Under Employee Stock Purchase Plan Description Shares reserved, description Stock Issued During Period, Shares, Employee Stock Purchase Plans Issuance of shares under an employee stock purchase plan (in shares) Shares issued under ESPP Development Stage Entities, Stock Issued, Shares, Issued for Cash Issuance of common stock under a securities purchase agreement (in share) Issuance of common stock under securities purchase agreements Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period Option exercises (in shares) Stock options exercised Stock Options, Exercised Stock Issued During Period, Value, Employee Stock Purchase Plan Issuance of shares under an employee stock purchase plan Development Stage Entities, Stock Issued, Value, Issued for Cash Issuance of common stock under securities purchase agreements Stock purchased, amount Stock Issued During Period, Value, Share-based Compensation, Net of Forfeitures Employee stock-based compensation Stock Issued During Period, Value, Stock Options Exercised Option exercises Equity Option [Member] Stock options Stock Plan Twenty Thirteen [Member] Stock Plan Twenty Thirteen [Member] Stock Plan 2013 Subsequent Event [Line Items] Subsequent Event [Line Items] Subsequent Event [Member] Subsequent Event Subsequent Events [Abstract] Subsequent Events [Abstract] Subsequent Events [Text Block] Subsequent Events Subsequent Event [Table] Subsequent Event [Table] Subsequent Event Type [Axis] Subsequent Event Type [Axis] Subsequent Event Type [Domain] Subsequent Event Type [Domain] Subsidiary, Sale of Stock [Axis] Subsidiary, Sale of Stock [Axis] Supplemental Balance Sheet Disclosures [Text Block] Balance Sheet Details Supplemental Cash Flow Information [Abstract] Supplemental disclosure of cash flow information: Tax Credit Carryforward, Amount Research tax credit carry-forwards Trading Symbol Trading Symbol Financial Instruments [Domain] Financial Instruments [Domain] Treasury Stock [Member] Treasury Stock Two Thousand Thirteen Plan [Member] Two Thousand Thirteen Plan [Member] 2013 Plan Uncategorized [Abstract] Uncategorized [Abstract] Uncategorized [Abstract] Underwriters Overallotment Shares Underwriters Overallotment Shares Over alloted units Underwritten Public Offering Price Value Underwritten Public Offering Price Value Public Offering proceeds Use of Estimates, Policy [Policy Text Block] Use of Estimates Value of Consideration Received Value of Consideration Received Additional consideration received for shares and warrants Warrant exercises. Warrant Exercises Warrant exercises Warrant exercises, shares. Warrant Exercises Shares Warrant exercises, shares Warrant [Member] Warrants Warrants expiration date. Warrants Expiration Date Warrant termination date Weighted Average Number of Shares Outstanding, Basic and Diluted Shares used to compute basic and diluted net loss per share Working Capital, Net Working Capital, Net Working capital