CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Cash flows from operating activities:
Net income (loss)	$ 92,105	$ (1,073)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation	348	2,080
Noncash lease expense	197	279
Loss on equity method investment	591
Stock-based compensation expense	4,051	3,883
Amortization of premium on short-term investments	38	162
Loss on disposal of property and equipment		6
Gain on sale of business	(131,249)
Changes in operating assets and liabilities:
Prepaid expenses and other current assets	507	(870)
Accounts payable	7,701	(100)
Accrued expenses and other liabilities	(4,988)	(4,540)
Accrued income taxes	967
Deferred revenue	(802)	(29,029)
Operating lease liabilities	(150)	(621)
Net cash used in operating activities	(30,684)	(29,823)
Cash flows from investing activities:
Purchases of short-term investments		(84,418)
Maturities of short-term investments	39,461
Proceeds from sale of business	130,000
Purchases of property and equipment	(1,149)	(817)
Net cash (used in) provided by investing activities	168,312	(85,235)
Cash flows from financing activities:
Proceeds from issuance of common stock pursuant to ATM, net of discounts and issuance costs		1,454
Proceeds from issuance of common stock pursuant to employee stock purchase plan	439	446
Proceeds from issuance of common stock from option exercises	1	143
Net cash provided by financing activities	440	2,043
Net change in cash, cash equivalents and restricted cash	138,068	(113,015)
Cash, cash equivalents and restricted cash, beginning of period	110,335	218,705
Cash, cash equivalents and restricted cash, end of period	248,403	105,690
Supplemental disclosures of noncash investing and financing activities:
Reclassification of liability for common stock vested		4
Property and equipment additions included in accounts payable	59	367
Property and equipment additions included in accrued expenses and other liabilities	5	164
Unrealized gain (loss) on available for sale securities, net	$ 7	$ (23)