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Employee Benefit Plans - Narrative (Detail) - USD ($) | 12 Months Ended
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Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Defined Benefit Plan Disclosure [Line Items] |  |  |
Minimum amount of employee contributions | $ 6,000 | $ 6,000 | $ 6,000
Defined contribution plan, employer matching contribution, percent of match | 6.00% | 6.00% | 6.00%
Discretionary contribution amount | $ 0 | $ 0 | $ 0
U.S. Plan |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Percentage to defer up base compensation of employees, effective from January 1, 2006 | 25.00% |  |
Amount to defer up bonus compensation of employees, effective from January 1, 2006 | $ 500,000 |  |
Percentage to defer up eligible bonus compensation, effective from January 1, 2006 | 25.00% |  |
Amount of compensation deferred in plan | $ 46,100,000 | 33,400,000 |
Percentage to Defer Up Cash Component of Director's Fees for Non-employee |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Percentage to defer up directors' fees | 100.00% |  |
Non-Employee Directors Voluntary Deferred Compensation Plan |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Amount of compensation deferred in plan | $ 1,200,000 | 1,000,000 |
Qualified Plan |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Percentage for employee pre-tax and/or after-tax contributions, minimum | 1.00% |  |
Percentage for employee pre-tax and/or after-tax contributions, maximum | 50.00% |  |
Defined contribution plan, cost | $ 8,800,000 | $ 7,800,000 | $ 6,800,000

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- Definition Deferred compensation plan percentage of bonus compensation by participants deferred in condition one, effective from inception date. + References No definition available. + Details
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