Investments (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Debt Securities, Available-for-sale [Line Items]
Adjusted Cost	$ 551,509	$ 717,043
Gross Unrealized Gains	18	411
Gross Unrealized Losses	(266)	(120)
Debt Securities, Available-for-sale	551,261	717,334
Cash equivalents [Member]
Debt Securities, Available-for-sale [Line Items]
Adjusted Cost	267,621	137,783
Debt Securities, Available-for-sale	267,621	137,783
Cash equivalents [Member] \| Money market funds [Member]
Debt Securities, Available-for-sale [Line Items]
Adjusted Cost	149,429	40,027
Debt Securities, Available-for-sale	149,429	40,027
Cash equivalents [Member] \| Time deposits [Member]
Debt Securities, Available-for-sale [Line Items]
Adjusted Cost	35,342	36,756
Debt Securities, Available-for-sale	35,342	36,756
Cash equivalents [Member] \| Commercial paper [Member]
Debt Securities, Available-for-sale [Line Items]
Adjusted Cost	77,850	61,000
Debt Securities, Available-for-sale	77,850	61,000
Cash equivalents [Member] \| Government and corporate bonds [Member]
Debt Securities, Available-for-sale [Line Items]
Adjusted Cost	5,000
Debt Securities, Available-for-sale	5,000
Short-term investments [Member]
Debt Securities, Available-for-sale [Line Items]
Adjusted Cost	252,721	442,277
Gross Unrealized Gains	18	259
Gross Unrealized Losses	(117)	(63)
Debt Securities, Available-for-sale	252,622	442,473
Short-term investments [Member] \| Time deposits [Member]
Debt Securities, Available-for-sale [Line Items]
Adjusted Cost	25,598	28,302
Debt Securities, Available-for-sale	25,598	28,302
Short-term investments [Member] \| Commercial paper [Member]
Debt Securities, Available-for-sale [Line Items]
Adjusted Cost	57,000	264,000
Gross Unrealized Gains		12
Gross Unrealized Losses	(14)	(19)
Debt Securities, Available-for-sale	56,986	263,993
Short-term investments [Member] \| Government and corporate bonds [Member]
Debt Securities, Available-for-sale [Line Items]
Adjusted Cost	170,123	149,975
Gross Unrealized Gains	18	247
Gross Unrealized Losses	(103)	(44)
Debt Securities, Available-for-sale	170,038	150,178
Long-term investments [Member] \| Government and corporate bonds [Member]
Debt Securities, Available-for-sale [Line Items]
Adjusted Cost	31,167	136,983
Gross Unrealized Gains		152
Gross Unrealized Losses	(149)	(57)
Debt Securities, Available-for-sale	$ 31,018	$ 137,078

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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