CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Cash Flows from Operating Activities:
Net loss	$ (7,388)	$ (73,947)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation	92	164
Share-based compensation	1,351	911
Change in fair value of contingent consideration	16,820	46,600
Changes in operating assets and liabilities:
Prepaid expenses and other assets	(899)	(421)
Accounts payable	(378)	1,216
Accrued expenses and other liabilities	1,714	1,761
Net Cash Used in Operating Activities	(22,328)	(23,716)
Cash Flows from Investing Activities:
Net Cash Used in Investing Activities	(8)	(137)
Cash Flows from Financing Activities:
Proceeds from issuance of common stock under ATM Offering, net of issuance costs	16,174	0
Proceeds from sales of common stock under 2014 ESPP	10	8
Proceeds from exercises of stock options	0	45
Proceeds from the issuance of common stock and common stock warrants, net of issuance costs	0	27,809
Proceeds from the exercise of common stock warrants	0	3,434
Net Cash Provided by Financing Activities	16,184	31,296
Net Increase (Decrease) in Cash, Cash Equivalents and Restricted Cash	(6,152)	7,443
Cash, Cash Equivalents and Restricted Cash - Beginning of Period	48,141	50,442
Cash, Cash Equivalents and Restricted Cash - End of Period	$ 41,989	57,885
Supplemental disclosure of non-cash activities
Accounting Standards Update [Extensible List]	us-gaap:AccountingStandardsUpdate201602Member
Right-of-use assets related to the adoption of ASC 842	$ 0	236
Right-of-use assets obtained in exchange for lease obligations	290	0
Cash paid for amounts included in the measurement of lease liabilities	113	115
Deemed dividend on adjustment of exercise price on certain warrants	$ 147	$ 0