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Employee Benefit Plans - Narrative (Detail) - USD ($) $ in Thousands |  | 3 Months Ended | 9 Months Ended |
--- | --- | --- | --- | ---
Jul. 01, 2018 | Sep. 30, 2021 | Sep. 30, 2020 | Sep. 30, 2021 | Sep. 30, 2020 | Dec. 31, 2020
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items] |  |  |  |  |  |
Deferred compensation plan liability |  | $ 35,715 |  | $ 35,715 |  | $ 26,390
Cash surrender value of policies |  | 36,306 |  | 36,306 |  | $ 26,832
Change in fair value of plan assets |  | (84) | $ 1,204 | 2,658 | $ 1,972 |
Change in fair value of deferred compensation liabilities |  | $ (159) | $ 1,085 | $ 2,526 | $ 1,942 |
U.S. |  |  |  |  |  |
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items] |  |  |  |  |  |
Vesting percentage of participants (in percentage) | 100.00% |  |  |  |  |
Employer discretionary vesting period | 2 years |  |  |  |  |
Earnings receivable minimum term | 2 years |  |  |  |  |
Earnings receivable lump sum or annual installment maximum terms | 15 years |  |  |  |  |
One-Year Anniversary of Approval of Contribution | U.S. |  |  |  |  |  |
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items] |  |  |  |  |  |
Employer discretionary vesting percentage (in percentage) | 50.00% |  |  |  |  |
Two-Year Anniversary of Approval of Contribution | U.S. |  |  |  |  |  |
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items] |  |  |  |  |  |
Employer discretionary vesting percentage (in percentage) | 50.00% |  |  |  |  |
Minimum | U.S. |  |  |  |  |  |
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items] |  |  |  |  |  |
Individual qualifying base compensation (in percentage) | 1.00% |  |  |  |  |
Individual qualifying bonus compensation (in percentage) | 1.00% |  |  |  |  |
Maximum | U.S. |  |  |  |  |  |
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items] |  |  |  |  |  |
Individual qualifying base compensation (in percentage) | 80.00% |  |  |  |  |
Individual qualifying bonus compensation (in percentage) | 100.00% |  |  |  |  |

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