Fair Value Measurements - Schedule of Fair Value Measurements for Items (Details) - USD ($)	Dec. 31, 2023	Dec. 31, 2022
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Warrants receivable	$ 0
Total assets at fair value	221,724,000	$ 327,766,000
Warrants receivable
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Warrants receivable	814,000	900,000
U.S. government and government agencies
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities	123,714,000	228,467,000
Corporate debt securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities	95,343,000	98,399,000
Other
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities	1,853,000
Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total assets at fair value	1,853,000	0
Level 1 | Warrants receivable
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Warrants receivable	0	0
Level 1 | U.S. government and government agencies
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities	0	0
Level 1 | Corporate debt securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities	0	0
Level 1 | Other
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities	1,853,000
Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total assets at fair value	219,057,000	326,866,000
Level 2 | Warrants receivable
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Warrants receivable	0	0
Level 2 | U.S. government and government agencies
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities	123,714,000	228,467,000
Level 2 | Corporate debt securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities	95,343,000	98,399,000
Level 2 | Other
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities	0
Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total assets at fair value	814,000	900,000
Level 3 | Warrants receivable
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Warrants receivable	814,000	900,000
Level 3 | U.S. government and government agencies
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities	0	0
Level 3 | Corporate debt securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities	0	$ 0
Level 3 | Other
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities	$ 0