CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	3 Months Ended				6 Months Ended		12 Months Ended
	Jun. 30, 2021	Mar. 31, 2021	Jun. 30, 2020	Mar. 31, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Cash Flows from Operating Activities:
Net (loss) income	$ (25,442)	$ (55,512)	$ (26,344)	$ 41,564	$ (80,954)	$ 15,220
Adjustments to reconcile net (loss) income to net cash used in operating activities:
Depreciation					64	61
Share-based compensation					2,217	898
Change in fair value of contingent consideration	13,600		18,480		61,760	(35,220)
Changes in operating assets and liabilities:
Accounts receivable (net)					(2,303)	0
Prepaid expenses and other assets					(20,287)	2,719
Accounts payable					(1,875)	(628)
Accrued expenses and other liabilities					1,262	(1,376)
Deferred revenue					(1,500)	0
Net cash used in operating activities					(41,616)	(18,326)	$ (30,800)
Cash Flows from Investing Activities:
Purchases of equipment					(49)	(8)
Net cash used in investing activities					(49)	(8)
Cash Flows from Financing Activities:
Proceeds from issuance of common stock under ATM Offering, net of issuance costs					136,804	7,953
Proceeds from exercises of stock options					39	0
Proceeds from the exercise of common stock warrants					469	0
Proceeds from sale of common stock pursuant to ESPP					0	1
Net cash provided by financing activities					137,312	7,954
Net Increase (decrease) in cash, cash equivalents and restricted cash					95,647	(10,380)
Cash, cash equivalents and restricted cash - beginning of period		$ 55,409		$ 48,141	55,409	48,141	48,141
Cash, cash equivalents and restricted cash - end of period	$ 151,056		$ 37,761		151,056	37,761	$ 55,409
Supplemental cash flow disclosure:
Cash paid for amounts included in the measurement of lease liabilities					87	75
Supplemental disclosure of non-cash investing activities:
Purchase of equipment included in accrued expenses					27	0
Supplemental disclosure of non-cash financing activities:
Deemed Dividend on adjustment of exercise price on certain warrants					$ 0	$ 147