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Investments - Cash Equivalents and Investments held at Fair Value (Detail) - Fair Value, Measurements [Member] - USD ($) $ in Thousands | Jun. 30, 2024 | Dec. 31, 2023
--- | --- | ---
Schedule of Available-for-sale Securities [Line Items] |  |
Total | $ 35,592 | $ 33,045
Quoted Prices in Active Market for Identical Assets (Level 1) [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Total | 35,592 | 33,045
Money Market Funds [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Cash equivalents | 5,433 | 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 | 5,433 | 5,302
Marketable Equity Securities - Various Industries [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Marketable equity securities | 955 | 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 | 955 | 905
Deferred Compensation Plan Assets [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Marketable equity securities | 29,204 | 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 | $ 29,204 | $ 26,838

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- Definition Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2 + Details
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