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Investments - Cash Equivalents and Investments held at Fair Value (Detail) - Fair Value, Measurements [Member] - USD ($) $ in Thousands	Mar. 31, 2025	Dec. 31, 2024
Schedule of Available-for-sale Securities [Line Items]
Total	$ 35,512	$ 37,597
Quoted Prices in Active Market for Identical Assets (Level 1) [Member]
Schedule of Available-for-sale Securities [Line Items]
Total	35,512	37,597
Money Market Funds [Member]
Schedule of Available-for-sale Securities [Line Items]
Cash equivalents	5,539	5,538
Money Market Funds [Member] | Quoted Prices in Active Market for Identical Assets (Level 1) [Member]
Schedule of Available-for-sale Securities [Line Items]
Cash equivalents	5,539	5,538
Marketable Equity Securities - Various Industries [Member]
Schedule of Available-for-sale Securities [Line Items]
Marketable equity securities	970	1,068
Marketable Equity Securities - Various Industries [Member] | Quoted Prices in Active Market for Identical Assets (Level 1) [Member]
Schedule of Available-for-sale Securities [Line Items]
Marketable equity securities	970	1,068
Deferred Compensation Plan Assets [Member]
Schedule of Available-for-sale Securities [Line Items]
Marketable equity securities	29,003	30,991
Deferred Compensation Plan Assets [Member] | Quoted Prices in Active Market for Identical Assets (Level 1) [Member]
Schedule of Available-for-sale Securities [Line Items]
Marketable equity securities	$ 29,003	$ 30,991

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