Investments - Cash Equivalents and Investments held at Fair Value (Detail) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale debt securities	$ 9,253	$ 30,066
Fair Value, Measurements [Member]
Schedule of Available-for-sale Securities [Line Items]
Total	33,227	70,259
Fair Value, Measurements [Member] \| Quoted Prices in Active Market for Identical Assets (Level 1) [Member]
Schedule of Available-for-sale Securities [Line Items]
Total	27,659	52,364
Fair Value, Measurements [Member] \| Significant Other Observable Inputs (Level 2) [Member]
Schedule of Available-for-sale Securities [Line Items]
Total	5,568	17,895
Money Market Funds [Member] \| Fair Value, Measurements [Member]
Schedule of Available-for-sale Securities [Line Items]
Cash equivalents	228	652
Money Market Funds [Member] \| Fair Value, Measurements [Member] \| Quoted Prices in Active Market for Identical Assets (Level 1) [Member]
Schedule of Available-for-sale Securities [Line Items]
Cash equivalents	228	652
Corporate Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale debt securities	2,462	10,747
Corporate Bonds [Member] \| Fair Value, Measurements [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale debt securities	2,462	10,747
Corporate Bonds [Member] \| Fair Value, Measurements [Member] \| Significant Other Observable Inputs (Level 2) [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale debt securities	2,462	10,747
Municipal Fixed-Rate Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale debt securities	180	1,551
Municipal Fixed-Rate Bonds [Member] \| Fair Value, Measurements [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale debt securities	180	1,551
Municipal Fixed-Rate Bonds [Member] \| Fair Value, Measurements [Member] \| Significant Other Observable Inputs (Level 2) [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale debt securities	180	1,551
Asset-Backed Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale debt securities	795	322
Asset-Backed Bonds [Member] \| Fair Value, Measurements [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale debt securities	795	322
Asset-Backed Bonds [Member] \| Fair Value, Measurements [Member] \| Significant Other Observable Inputs (Level 2) [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale debt securities	795	322
Mortgage/Agency-Backed Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale debt securities	1,748	4,736
Mortgage/Agency-Backed Bonds [Member] \| Fair Value, Measurements [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale debt securities	1,748	4,736
Mortgage/Agency-Backed Bonds [Member] \| Fair Value, Measurements [Member] \| Significant Other Observable Inputs (Level 2) [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale debt securities	1,748	4,736
U.S. Government Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale debt securities	3,685	12,171
U.S. Government Bonds [Member] \| Fair Value, Measurements [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale debt securities	3,685	12,171
U.S. Government Bonds [Member] \| Fair Value, Measurements [Member] \| Quoted Prices in Active Market for Identical Assets (Level 1) [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale debt securities	3,685	12,171
Foreign Government Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale debt securities	383	539
Foreign Government Bonds [Member] \| Fair Value, Measurements [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale debt securities	383	539
Foreign Government Bonds [Member] \| Fair Value, Measurements [Member] \| Significant Other Observable Inputs (Level 2) [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale debt securities	383	539
Marketable Equity Securities - Various Industries [Member] \| Fair Value, Measurements [Member]
Schedule of Available-for-sale Securities [Line Items]
Marketable equity securities	804	12,606
Marketable Equity Securities - Various Industries [Member] \| Fair Value, Measurements [Member] \| Quoted Prices in Active Market for Identical Assets (Level 1) [Member]
Schedule of Available-for-sale Securities [Line Items]
Marketable equity securities	804	12,606
Deferred Compensation Plan Assets [Member] \| Fair Value, Measurements [Member]
Schedule of Available-for-sale Securities [Line Items]
Marketable equity securities	22,942	26,935
Deferred Compensation Plan Assets [Member] \| Fair Value, Measurements [Member] \| Quoted Prices in Active Market for Identical Assets (Level 1) [Member]
Schedule of Available-for-sale Securities [Line Items]
Marketable equity securities	$ 22,942	$ 26,935

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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