Fair Value Measurements - Assets and Liabilities Measured at Fair Value on Recurring Basis (Details) - Recurring Basis - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Assets:
Total	$ 999,132	$ 1,077,550
Level 1
Assets:
Total	999,132	1,077,550
Level 2
Assets:
Total	0	0
Level 3
Assets:
Total	0	0
Money market funds
Assets:
Cash equivalents	999,132	1,077,550
Money market funds | Level 1
Assets:
Cash equivalents	999,132	1,077,550
Money market funds | Level 2
Assets:
Cash equivalents	0	0
Money market funds | Level 3
Assets:
Cash equivalents	$ 0	$ 0