Fair Value Measurements - Summary of Company's Investments (Detail) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Schedule Of Available For Sale Securities [Line Items]
Investments, Amortized cost	$ 135,973	$ 134,903
Investments, Gross unrealized gains	654	673
Investments, Gross unrealized losses	(796)	(715)
Investments, Fair value	135,831	134,861
U.S. Treasuries [Member]
Schedule Of Available For Sale Securities [Line Items]
Trading securities, Amortized cost	99,682	99,236
Trading securities, Gross unrealized gains		446
Trading securities, Gross unrealized losses	(255)
Trading securities, Fair value	99,427	99,682
Investments, Fair value	99,427	99,682
Mutual Funds Held In Rabbi Trust [Member]
Schedule Of Available For Sale Securities [Line Items]
Trading securities, Amortized cost	10,818	10,962
Trading securities, Gross unrealized gains	629	172
Trading securities, Gross unrealized losses	(432)	(649)
Trading securities, Fair value	11,015	10,485
Investments, Fair value	11,015	10,485
Corporate Debt [Member]
Schedule Of Available For Sale Securities [Line Items]
Trading securities, Amortized cost	25,473	24,705
Trading securities, Gross unrealized gains	25	55
Trading securities, Gross unrealized losses	(109)	(66)
Trading securities, Fair value	25,389	24,694
Investments, Fair value	$ 25,389	$ 24,694

Marketable securities accumulated gross unrealized gain before tax.

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Marketable securities amortized cost.

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Amount of investment in marketable security.

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