Fair Value Measurements - Summary of Company's Investments and Securities Positions (Detail) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Schedule Of Available For Sale Securities [Line Items]
Investments, Amortized cost	$ 164,934	$ 134,903
Investments, Gross unrealized gains	2,358	673
Investments, Gross unrealized losses	(79)	(715)
Investments, Fair value	167,213	134,861
U.S. Treasuries [Member]
Schedule Of Available For Sale Securities [Line Items]
Trading securities, Amortized cost	100,499	99,236
Trading securities, Gross unrealized gains	701	446
Trading securities, Gross unrealized losses	(17)
Trading securities, Fair value	101,183	99,682
Investments, Fair value	101,183	99,682
Mutual Funds Held In Rabbi Trust [Member]
Schedule Of Available For Sale Securities [Line Items]
Trading securities, Amortized cost	9,695	10,962
Trading securities, Gross unrealized gains	1,373	172
Trading securities, Gross unrealized losses		(649)
Trading securities, Fair value	11,068	10,485
Investments, Fair value	11,068	10,485
Corporate Debt [Member]
Schedule Of Available For Sale Securities [Line Items]
Trading securities, Amortized cost	54,740	24,705
Trading securities, Gross unrealized gains	284	55
Trading securities, Gross unrealized losses	(62)	(66)
Trading securities, Fair value	54,962	24,694
Investments, Fair value	$ 54,962	$ 24,694

Marketable securities accumulated gross unrealized gain before tax.

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Marketable securities accumulated gross unrealized loss before tax.

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Marketable securities amortized cost.

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Amount of investment in marketable security.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of investment in debt security measured at fair value with change in fair value recognized in net income (trading).

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