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Supplemental Disclosures of Cash Flow Information - Additional Information (Detail) - Qualified Contributory Savings and Thrift 401(k) Plan [Member] - USD ($) $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2024 | Mar. 31, 2023 | Dec. 31, 2023 | Dec. 31, 2022
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Matching contributions by employer, percentage | 100.00% |  |  |
Percentage of eligible compensation for matching contributions by employer | 5.00% | 5.00% |  |
Matching contributions vesting schedule | 5 years |  |  |
Contribution expense to plan | $ 26.1 | $ 21.0 |  |
Employer match on eligible compensation |  |  | 5.00% | 5.00%

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- Definition Amount of cost for defined contribution plan. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 70 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480794/715-70-50-1 + Details
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- Details
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