CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Cash Flows from Operating Activities:
Net income (loss)	$ 41,564	$ (6,480)
Adjustments to reconcile net income (loss) to net cash used in operating activities:
Depreciation	31	49
Share-based compensation	407	326
Change in fair value of contingent consideration	(53,700)	(1,000)
Changes in operating assets and liabilities:
Prepaid expenses and other assets	4,011	(1,912)
Accounts payable	166	316
Accrued expenses and other liabilities	(1,317)	709
Net Cash Used in Operating Activities	(8,838)	(7,992)	$ (37,500)
Cash Flows from Investing Activities:
Net Cash Used in Investing Activities	0	0
Cash Flows from Financing Activities:
Proceeds from issuance of common stock under ATM Offering, net of issuance costs	3,179	0
Proceeds from sales of common stock under 2014 ESPP	1	7
Net Cash Provided by Financing Activities	3,180	7
Net Decrease in Cash, Cash Equivalents and Restricted Cash	(5,658)	(7,985)
Cash, Cash Equivalents and Restricted Cash - Beginning of Period	48,141	50,442	50,442
Cash, Cash Equivalents and Restricted Cash - End of Period	42,483	42,457	$ 48,141
Supplemental disclosure of non-cash operating activities:
Right-of-use assets related to the adoption of ASC 842	0	236
Cash paid for amounts included in the measurement of lease liabilities	$ 38	$ 38