General - Cash, Cash Equivalents and Short-term Investments (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Cash and cash equivalents
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 406,887
Amortized Cost		$ 10,712
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	406,887	10,712
Cash and cash equivalents \| Money market funds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	406,887
Amortized Cost		10,712
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	406,887	10,712
Marketable securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	8,010	34,113
Gross Unrealized Gains		4
Gross Unrealized Losses	0
Fair Value	8,010	34,117
Marketable securities \| US Treasury securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	8,010	34,113
Gross Unrealized Gains		4
Gross Unrealized Losses	0
Fair Value	8,010	34,117
Short-term deposits
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	2,276
Amortized Cost		30,053
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	2,276	30,053
Short-term deposits \| Term bank deposits
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	2,276
Amortized Cost		30,053
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	$ 2,276	$ 30,053

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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