Cash, Cash Equivalents and Investment Debt Securities (Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value) (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Total available for sale securities, Less than 12 months, Fair Value	$ 345,758	$ 295,608
Total available for sale securities Less than 12 months, Gross Unrealized Holding Losses	(1,805)	(296)
Total available for sale securities, More than 12 months, Fair Value	999	0
Total available for sale securities more than 12 months, Gross Unrealized Holding Losses	(1)	0
Available-for-sale securities, Total Fair Value	346,757	295,608
Available-for-sale securities, Total Gross Unrealized Losses	(1,806)	(296)
Commercial paper
Total available for sale securities, Less than 12 months, Fair Value	143,612	81,464
Total available for sale securities Less than 12 months, Gross Unrealized Holding Losses	(320)	(49)
Total available for sale securities, More than 12 months, Fair Value	0	0
Total available for sale securities more than 12 months, Gross Unrealized Holding Losses	0	0
Available-for-sale securities, Total Fair Value	143,612	81,464
Available-for-sale securities, Total Gross Unrealized Losses	(320)	(49)
Corporate debt securities
Total available for sale securities, Less than 12 months, Fair Value	178,637	196,120
Total available for sale securities Less than 12 months, Gross Unrealized Holding Losses	(1,318)	(245)
Total available for sale securities, More than 12 months, Fair Value	999	0
Total available for sale securities more than 12 months, Gross Unrealized Holding Losses	(1)	0
Available-for-sale securities, Total Fair Value	179,636	196,120
Available-for-sale securities, Total Gross Unrealized Losses	(1,319)	(245)
Municipal bonds
Total available for sale securities, Less than 12 months, Fair Value		5,027
Total available for sale securities Less than 12 months, Gross Unrealized Holding Losses		(1)
Total available for sale securities, More than 12 months, Fair Value		0
Total available for sale securities more than 12 months, Gross Unrealized Holding Losses		0
Available-for-sale securities, Total Fair Value		5,027
Available-for-sale securities, Total Gross Unrealized Losses		(1)
U.S. government agency bonds
Total available for sale securities, Less than 12 months, Fair Value	3,442
Total available for sale securities Less than 12 months, Gross Unrealized Holding Losses	(58)
Total available for sale securities, More than 12 months, Fair Value	0
Total available for sale securities more than 12 months, Gross Unrealized Holding Losses	0
Available-for-sale securities, Total Fair Value	3,442
Available-for-sale securities, Total Gross Unrealized Losses	(58)
U.S Treasury securities
Total available for sale securities, Less than 12 months, Fair Value	20,067	12,997
Total available for sale securities Less than 12 months, Gross Unrealized Holding Losses	(109)	(1)
Total available for sale securities, More than 12 months, Fair Value	0	0
Total available for sale securities more than 12 months, Gross Unrealized Holding Losses	0	0
Available-for-sale securities, Total Fair Value	20,067	12,997
Available-for-sale securities, Total Gross Unrealized Losses	$ (109)	$ (1)

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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