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Deferred Compensation - Additional Information (Detail) - USD ($) shares in Millions | 3 Months Ended | 12 Months Ended
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Mar. 31, 2024 | Mar. 31, 2023 | Mar. 31, 2022 | Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
Investments And Employee Deferred Compensation Plan [Line Items] |  |  |  |  |  |
Deferred Equity Participation Plan, distributions to key executives, age |  |  |  | age 62 (or the one-year anniversary of the date of the grant for participants over the age of 61 as of the grant date) or upon or after their actual retirement if later. |  |
Deferred Equity Participation Sub-plans, distributions requisite service description |  |  |  | we annually make awards under sub-plans of the DEPP for certain production staff, which generally provide for vesting and/or distributions no sooner than five years from the date of awards, although certain awards vest and/or distribute after the earlier of fifteen years or the participant reaching age 65. |  |
Deferred Equity Participation Sub-plans, distributions to key executives, age |  |  |  | age 65 |  |
Deferred Equity Participation Plan (DEPP) [Member] |  |  |  |  |  |
Investments And Employee Deferred Compensation Plan [Line Items] |  |  |  |  |  |
Awards approved by committee, value | $ 23,200,000 | $ 25,100,000 | $ 26,300,000 |  |  |
Charge to compensation expenses related to awards |  |  |  | $ 20,900,000 | $ 21,700,000 | $ 18,500,000
Unearned deferred compensation, value |  |  |  | $ 77,000,000 | $ 81,100,000 |
Unearned deferred compensation, shares |  |  |  | 2.2 | 2.2 |
Total intrinsic value of unvested equity based awards |  |  |  | $ 616,400,000 | $ 504,900,000 |
Cash and equity awards with aggregate fair value vested and distributed to participants |  |  |  | 40,400,000 | 78,100,000 | 45,600,000
Deferred Equity Participation Plan Sub Plans [Member] |  |  |  |  |  |
Investments And Employee Deferred Compensation Plan [Line Items] |  |  |  |  |  |
Awards approved by committee, value |  |  |  | 2,300,000 | 3,000,000 | 1,900,000
Charge to compensation expenses related to awards |  |  |  | 2,100,000 | 2,600,000 | 2,300,000
Distributions from the sub-plans |  |  |  | 3,000,000 | 13,800,000 | 0
Deferred Cash Participation Plan (DCPP) [Member] |  |  |  |  |  |
Investments And Employee Deferred Compensation Plan [Line Items] |  |  |  |  |  |
Awards approved by committee, value | $ 8,100,000 | $ 9,800,000 | $ 8,300,000 |  |  |
Charge to compensation expenses related to awards |  |  |  | 19,300,000 | 17,300,000 | 13,400,000
Cash and equity awards with aggregate fair value vested and distributed to participants |  |  |  | $ 43,800,000 | $ 23,200,000 | $ 16,900,000

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