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Deferred Compensation - Additional Information (Detail) - USD ($) shares in Millions, $ in Millions | 3 Months Ended | 6 Months Ended | 12 Months Ended
--- | --- | --- | ---
Jun. 30, 2024 | Mar. 31, 2024 | Jun. 30, 2023 | Mar. 31, 2023 | Jun. 30, 2024 | Jun. 30, 2023 | Dec. 31, 2023
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 |  | $ 23.2 |  | $ 25.1 |  |  |
Charge to compensation expenses related to awards | $ 5.6 |  | $ 5.9 |  | $ 9.6 | $ 9.9 |
Unearned deferred compensation, value |  |  |  |  | $ 95.5 |  | $ 81.1
Unearned deferred compensation, shares |  |  |  |  | 2.3 |  | 2.2
Total intrinsic value of unvested equity based awards |  |  |  |  | $ 584.4 |  | $ 504.9
Cash and equity awards with aggregate fair value vested and distributed to participants |  |  |  |  | 17.9 | 9.4 |
Deferred Equity Participation Plan Sub Plans [Member] |  |  |  |  |  |  |
Investments And Employee Deferred Compensation Plan [Line Items] |  |  |  |  |  |  |
Awards approved by committee, value |  | 2.3 |  | 3.0 |  |  |
Charge to compensation expenses related to awards | 0.6 |  | 0.8 |  | 1.1 | 1.4 |
Distributions from the sub-plans |  |  |  |  | 2.3 | 6.4 |
Deferred Cash Participation Plan (DCPP) [Member] |  |  |  |  |  |  |
Investments And Employee Deferred Compensation Plan [Line Items] |  |  |  |  |  |  |
Awards approved by committee, value |  | $ 8.1 |  | $ 9.8 |  |  |
Charge to compensation expenses related to awards | $ 5.1 |  | $ 4.2 |  | 9.9 | 8.0 |
Cash and equity awards with aggregate fair value vested and distributed to participants |  |  |  |  | $ 13.6 | $ 19.5 |

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- Definition Amount of expense for award under share-based payment arrangement. Excludes amount capitalized. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 718 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 14.F) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479830/718-10-S99-1 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 718 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (h)(1)(i) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480429/718-10-50-2 + Details
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- Definition Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 718 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (d)(2) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480429/718-10-50-2 + Details
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