Basis of Presentation	9 Months Ended
Sep. 30, 2019
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation	Basis of Presentation The accompanying Condensed Consolidated Financial Statements of the Company have been prepared in accordance with the instructions to Form 10-Q and Article 10 of Regulation S-X. These statements, however, are condensed and do not include all disclosures required by accounting principles generally accepted in the U.S. (“GAAP”), for complete financial statements and should be read in conjunction with the Company’s Annual Report on Form 10-K for the year ended December 31, 2018 as filed with the Securities and Exchange Commission (“SEC”), on March 26, 2019. In the opinion of the Company, the unaudited financial statements contain all adjustments (all of which were considered normal and recurring) necessary for a fair statement of the Company’s financial position at September 30, 2019; the results of operations for the three and nine-month periods ended September 30, 2019 and 2018; stockholders' deficit for the three and nine-month periods ended September 30, 2019 and 2018 and the cash flows for the nine-month periods ended September 30, 2019 and 2018. The Condensed Consolidated Balance Sheet at December 31, 2018 was derived from audited annual financial statements but does not contain all of the footnote disclosures from the annual financial statements. In accordance with Accounting Standards Update (“ASU”) 2014-15, Disclosure of Uncertainties about an Entity’s Ability to Continue as a Going Concern (Subtopic 205-40), the Company has evaluated whether there are conditions and events, considered in the aggregate, that raise substantial doubt about the Company’s ability to continue as a going concern within one year after the date that the Consolidated Financial Statements are issued. The Company anticipates that its $28.0 million of existing cash, cash equivalents and investments at September 30, 2019 should enable it to maintain its planned operations into the second half of 2020. Based on the Company's available cash resources, recurring losses and cash outflows from operations since inception, an expectation of continuing operating losses and cash outflows from operations for the foreseeable future and the need to raise additional capital to finance our future operations, the Company concluded it does not have sufficient cash on hand to support current operations within the next 12 months from the date of filing this Quarterly Report on Form 10-Q. These factors raise substantial doubt regarding the Company’s ability to continue as a going concern. The Company expects to finance its operations through its current at-the-market sale agreement with Cowen and Company, LLC, or Cowen or other potential equity financings, debt financings or other capital sources. However, the Company may not be successful in securing additional financing on acceptable terms, or at all. The preparation of the Company’s Condensed Consolidated Financial Statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts and disclosure of certain assets and liabilities at the balance sheet date. Such estimates include the performance obligations under the Company’s collaboration agreements; the estimated repayment term of the Company’s debt and related short- and long-term classification; the fair value of the Company’s debt; the collectability of receivables; the carrying value of property and equipment and intangible assets; and the assumptions used in the Company’s valuation of stock-based compensation and the value of certain investments and liabilities. Actual results may differ from such estimates. These interim results are not necessarily indicative of results to be expected for a full year or subsequent interim periods. Reclassifications and Revision Certain prior period amounts have been reclassified to conform with the current period presentation. Reclassifications had no material impact on previously reported results of operations, financial position or cash flows. A revision was made to the Condensed Consolidated Statement of Cash Flows for the three months ended March 31, 2019 to correctly reflect the prepayment fees associated with the termination of the credit agreement with HealthCare Royalty Partners, III, L.P. This correction reduced the net cash used in operating activities and reduced the net cash provided by financing activities for the three months ended March 31, 2019 by $3.4 million, from the amounts previously reported. The revision to the Condensed Consolidated Statement of Cash Flows noted above represents an error that is not deemed to be material to the prior period Condensed Consolidated Financial Statements.

Basis of Presentation

The accompanying Condensed Consolidated Financial Statements of the Company have been prepared in accordance with the instructions to Form 10-Q and Article 10 of Regulation S-X. These statements, however, are condensed and do not include all disclosures required by accounting principles generally accepted in the U.S. (“GAAP”), for complete financial statements and should be read in conjunction with the Company’s Annual Report on Form 10-K for the year ended December 31, 2018 as filed with the Securities and Exchange Commission (“SEC”), on March 26, 2019.

In the opinion of the Company, the unaudited financial statements contain all adjustments (all of which were considered normal and recurring) necessary for a fair statement of the Company’s financial position at September 30, 2019; the results of operations for the three and nine-month periods ended September 30, 2019 and 2018; stockholders' deficit for the three and nine-month periods ended September 30, 2019 and 2018 and the cash flows for the nine-month periods ended September 30, 2019 and 2018. The Condensed Consolidated Balance Sheet at December 31, 2018 was derived from audited annual financial statements but does not contain all of the footnote disclosures from the annual financial statements.

In accordance with Accounting Standards Update (“ASU”) 2014-15, Disclosure of Uncertainties about an Entity’s Ability to Continue as a Going Concern (Subtopic 205-40), the Company has evaluated whether there are conditions and events, considered in the aggregate, that raise substantial doubt about the Company’s ability to continue as a going concern within one year after the date that the Consolidated Financial Statements are issued.

The Company anticipates that its $28.0 million of existing cash, cash equivalents and investments at September 30, 2019 should enable it to maintain its planned operations into the second half of 2020. Based on the Company's available cash resources, recurring losses and cash outflows from operations since inception, an expectation of continuing operating losses and cash outflows from operations for the foreseeable future and the need to raise additional capital to finance our future operations, the Company concluded it does not have sufficient cash on hand to support current operations within the next 12 months from the date of filing this Quarterly Report on Form 10-Q. These factors raise substantial doubt regarding the Company’s ability to continue as a going concern. The Company expects to finance its operations through its current at-the-market sale agreement with Cowen and Company, LLC, or Cowen or other potential equity financings, debt financings or other capital sources. However, the Company may not be successful in securing additional financing on acceptable terms, or at all.

The preparation of the Company’s Condensed Consolidated Financial Statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts and disclosure of certain assets and liabilities at the balance sheet date. Such estimates include the performance obligations under the Company’s collaboration agreements; the estimated repayment term of the Company’s debt and related short- and long-term classification; the fair value of the Company’s debt; the collectability of receivables; the carrying value of property and equipment and intangible assets; and the assumptions used in the Company’s valuation of stock-based compensation and the value of certain investments and liabilities. Actual results may differ from such estimates.

These interim results are not necessarily indicative of results to be expected for a full year or subsequent interim periods.

Reclassifications and Revision

Certain prior period amounts have been reclassified to conform with the current period presentation. Reclassifications had no material impact on previously reported results of operations, financial position or cash flows.

A revision was made to the Condensed Consolidated Statement of Cash Flows for the three months ended March 31, 2019 to correctly reflect the prepayment fees associated with the termination of the credit agreement with HealthCare Royalty Partners, III, L.P. This correction reduced the net cash used in operating activities and reduced the net cash provided by financing activities for the three months ended March 31, 2019 by $3.4 million, from the amounts previously reported. The revision to the Condensed Consolidated Statement of Cash Flows noted above represents an error that is not deemed to be material to the prior period Condensed Consolidated Financial Statements.