Fair Value Measurements - Marketable Debt Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Amortized Cost	$ 78,573	$ 95,466
Gross Unrealized Gains	123	387
Gross Unrealized Losses	(3,056)	(2,722)
Estimated Fair Value	75,640	93,131
Credit Impairment Losses	0	0
Municipal bonds — non-taxable
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Amortized Cost		95,466
Gross Unrealized Gains		387
Gross Unrealized Losses		(2,722)
Estimated Fair Value		93,131
Credit Impairment Losses		0
Unrestricted
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Amortized Cost	53,531
Gross Unrealized Gains	0
Gross Unrealized Losses	(2,996)
Estimated Fair Value	50,535	93,131
Credit Impairment Losses	0
Unrestricted | Municipal bonds — taxable
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Amortized Cost	10,276
Gross Unrealized Gains	0
Gross Unrealized Losses	(676)
Estimated Fair Value	9,600
Credit Impairment Losses	0
Unrestricted | Municipal bonds — non-taxable
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Amortized Cost	43,255
Gross Unrealized Gains	0
Gross Unrealized Losses	(2,320)
Estimated Fair Value	40,935
Credit Impairment Losses	0
Restricted
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Amortized Cost	25,042
Gross Unrealized Gains	123
Gross Unrealized Losses	(60)
Estimated Fair Value	25,105	$ 0
Credit Impairment Losses	0
Restricted | Municipal bonds — taxable
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Amortized Cost	9,131
Gross Unrealized Gains	40
Gross Unrealized Losses	(41)
Estimated Fair Value	9,130
Credit Impairment Losses
Restricted | U.S. treasury bonds
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Amortized Cost	7,276
Gross Unrealized Gains	38
Gross Unrealized Losses	(5)
Estimated Fair Value	7,309
Credit Impairment Losses
Restricted | U.S. government agency bonds
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Amortized Cost	1,208
Gross Unrealized Gains	10
Gross Unrealized Losses	0
Estimated Fair Value	1,218
Credit Impairment Losses
Restricted | International fixed income bonds
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Amortized Cost	647
Gross Unrealized Gains	5
Gross Unrealized Losses	0
Estimated Fair Value	652
Credit Impairment Losses
Restricted | Corporate bonds
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Amortized Cost	6,780
Gross Unrealized Gains	30
Gross Unrealized Losses	(14)
Estimated Fair Value	6,796
Credit Impairment Losses