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Investments - Cash Equivalents and Investments held at Fair Value (Detail) - Fair Value, Measurements [Member] - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Schedule of Available-for-sale Securities [Line Items]
Total	$ 37,597	$ 33,045
Quoted Prices in Active Market for Identical Assets (Level 1) [Member]
Schedule of Available-for-sale Securities [Line Items]
Total	37,597	33,045
Money Market Funds [Member]
Schedule of Available-for-sale Securities [Line Items]
Cash equivalents	5,538	5,302
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	5,538	5,302
Marketable Equity Securities - Various Industries [Member]
Schedule of Available-for-sale Securities [Line Items]
Marketable equity securities	1,068	905
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	1,068	905
Deferred Compensation Plan Assets [Member]
Schedule of Available-for-sale Securities [Line Items]
Marketable equity securities	30,991	26,838
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	$ 30,991	$ 26,838

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