Financial Instruments - Cash, Cash Equivalents and Marketable Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Amortized Cost
Cash, cash equivalents and marketable securities	$ 1,123,786	$ 1,297,157
Gross Unrealized Gains
Cash, cash equivalents and marketable securities	3	9
Gross Unrealized Losses
Cash, cash equivalents and marketable securities	(3,226)	(504)
Fair Value
Cash and cash equivalents	926,119	1,099,370
Cash, cash equivalents and marketable securities	1,120,563	1,296,662
Cash
Amortized Cost
Cash and cash equivalents	689,175	754,802
Fair Value
Cash and cash equivalents	689,175	754,802
Cash and Cash Equivalents
Fair Value
Cash, cash equivalents and marketable securities	926,119	1,099,370
Cash and Cash Equivalents \| Cash
Fair Value
Cash and cash equivalents	689,175	754,802
Marketable securities, short-term
Fair Value
Cash, cash equivalents and marketable securities	86,749	71,972
Marketable securities, long-term
Fair Value
Cash, cash equivalents and marketable securities	107,695	125,320
Money market funds
Amortized Cost
Cash and cash equivalents	236,960	343,012
Gross Unrealized Losses
Cash and cash equivalents	(16)	(2)
Fair Value
Cash and cash equivalents	236,944	343,010
Money market funds \| Cash and Cash Equivalents
Fair Value
Cash and cash equivalents	236,944	343,010
Corporate bonds
Amortized Cost
Marketable securities	116,307	115,507
Gross Unrealized Gains
Marketable securities	3	9
Gross Unrealized Losses
Marketable securities	(2,389)	(398)
Fair Value
Marketable securities	113,921	115,118
Corporate bonds \| Cash and Cash Equivalents
Fair Value
Marketable securities		1,042
Corporate bonds \| Marketable securities, short-term
Fair Value
Marketable securities	41,164	35,065
Corporate bonds \| Marketable securities, long-term
Fair Value
Marketable securities	72,757	79,011
U.S. government treasury bonds
Amortized Cost
Marketable securities	46,638	42,976
Gross Unrealized Gains
Marketable securities	0	0
Gross Unrealized Losses
Marketable securities	(511)	(48)
Fair Value
Marketable securities	46,127	42,928
U.S. government treasury bonds \| Marketable securities, short-term
Fair Value
Marketable securities	31,055	22,251
U.S. government treasury bonds \| Marketable securities, long-term
Fair Value
Marketable securities	15,072	20,677
Asset-backed securities
Amortized Cost
Marketable securities	27,453	32,031
Gross Unrealized Gains
Marketable securities	0	0
Gross Unrealized Losses
Marketable securities	(197)	(40)
Fair Value
Marketable securities	27,256	31,991
Asset-backed securities \| Marketable securities, short-term
Fair Value
Marketable securities	10,984	10,999
Asset-backed securities \| Marketable securities, long-term
Fair Value
Marketable securities	16,272	20,992
Municipal bonds
Amortized Cost
Marketable securities	6,049	7,628
Gross Unrealized Gains
Marketable securities	0	0
Gross Unrealized Losses
Marketable securities	(77)	(15)
Fair Value
Marketable securities	5,972	7,613
Municipal bonds \| Cash and Cash Equivalents
Fair Value
Marketable securities		516
Municipal bonds \| Marketable securities, short-term
Fair Value
Marketable securities	3,546	3,657
Municipal bonds \| Marketable securities, long-term
Fair Value
Marketable securities	2,426	3,440
U.S. government agency bonds
Amortized Cost
Marketable securities	1,204	1,201
Gross Unrealized Gains
Marketable securities	0	0
Gross Unrealized Losses
Marketable securities	(36)	(1)
Fair Value
Marketable securities	1,168	1,200
U.S. government agency bonds \| Marketable securities, long-term
Fair Value
Marketable securities	$ 1,168	$ 1,200

Cash And Cash Equivalents, Accumulated Gross Unrealized Loss, Before Tax

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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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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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