Financial Instruments - Available-for-sale Debt Securities (Details) - USD ($)	Dec. 31, 2023	Dec. 31, 2022
Debt Securities, Available-for-Sale, Unrealized Loss Position [Abstract]
Fair Value, Less Than 12 Months	$ 58,944,000	$ 218,379,000
Fair Value, 12 Months or Greater	1,027,000
Fair Value, Total	59,971,000
Debt Securities, Available-for-Sale, Unrealized Loss Position, Accumulated Loss [Abstract]
Gross Unrealized Losses, Less Than 12 Months	(40,000)	(414,000)
Gross Unrealized Losses, 12 Months or Greater	(4,000)	0
Gross Unrealized Losses, Total	(44,000)
Asset-backed securities
Debt Securities, Available-for-Sale, Unrealized Loss Position [Abstract]
Fair Value, Less Than 12 Months	3,211,000	6,598,000
Fair Value, 12 Months or Greater	1,027,000
Fair Value, Total	4,238,000
Debt Securities, Available-for-Sale, Unrealized Loss Position, Accumulated Loss [Abstract]
Gross Unrealized Losses, Less Than 12 Months	(6,000)	(29,000)
Gross Unrealized Losses, 12 Months or Greater	(4,000)
Gross Unrealized Losses, Total	(10,000)
Corporate notes and obligations
Debt Securities, Available-for-Sale, Unrealized Loss Position [Abstract]
Fair Value, Less Than 12 Months	40,527,000	55,136,000
Fair Value, 12 Months or Greater	0
Fair Value, Total	40,527,000
Debt Securities, Available-for-Sale, Unrealized Loss Position, Accumulated Loss [Abstract]
Gross Unrealized Losses, Less Than 12 Months	(21,000)	(202,000)
Gross Unrealized Losses, 12 Months or Greater	0
Gross Unrealized Losses, Total	(21,000)
U.S. treasury securities
Debt Securities, Available-for-Sale, Unrealized Loss Position [Abstract]
Fair Value, Less Than 12 Months	7,397,000	149,128,000
Fair Value, 12 Months or Greater	0
Fair Value, Total	7,397,000
Debt Securities, Available-for-Sale, Unrealized Loss Position, Accumulated Loss [Abstract]
Gross Unrealized Losses, Less Than 12 Months	(8,000)	(180,000)
Gross Unrealized Losses, 12 Months or Greater	0
Gross Unrealized Losses, Total	(8,000)
U.S. agency securities
Debt Securities, Available-for-Sale, Unrealized Loss Position [Abstract]
Fair Value, Less Than 12 Months	7,809,000	7,517,000
Fair Value, 12 Months or Greater	0
Fair Value, Total	7,809,000
Debt Securities, Available-for-Sale, Unrealized Loss Position, Accumulated Loss [Abstract]
Gross Unrealized Losses, Less Than 12 Months	(5,000)	$ (3,000)
Gross Unrealized Losses, 12 Months or Greater	0
Gross Unrealized Losses, Total	$ (5,000)

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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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