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)	$ (42,077)	$ 30,713
Adjustments to reconcile net income (loss) to net cash used in operating activities:
Stock-based compensation expense	11,661	7,273
Non-cash lease expense	16
Depreciation and amortization expense	7	7
Changes in operating assets and liabilities:
Prepaid expenses and other current assets	275	1,151
Other assets		(356)
Accounts payable	(877)	3,732
Accrued expenses and other liabilities	(28,014)	6,628
Deferred revenue		(65,985)
Net cash used in operating activities	(59,009)	(16,837)
Cash flows from investing activities
Additions to property and equipment	(44)
Net cash used in investing activities	(44)
Cash flows from financing activities
Proceeds from issuance of common stock for exercise of stock options	223	471
Net cash provided by financing activities	223	471
Net increase (decrease) in cash, cash equivalents and restricted cash	(58,830)	(16,366)
Cash, cash equivalents and restricted cash at the beginning of period	764,680	850,224
Cash, cash equivalents and restricted cash at the end of period	705,850	833,858
Cash, cash equivalents and restricted cash at the end of period:
Cash and cash equivalents	705,545	833,751
Restricted cash	305	107
Cash, cash equivalents and restricted cash at the end of period	705,850	$ 833,858
Supplemental disclosure of noncash financing activities
Property and equipment purchases unpaid at period end	702
Right of use assets obtained in exchange for operating lease liabilities	$ 2,938