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Restricted Stock, Performance Share and Cash Awards - Additional Information (Detail) $ in Millions |  |  |  |  | 3 Months Ended | 12 Months Ended |
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Mar. 01, 2024 USD ($) shares | Mar. 15, 2023 USD ($) shares | May 10, 2022 shares | Mar. 15, 2022 USD ($) shares | Dec. 31, 2024 USD ($) shares | Sep. 30, 2024 shares | Jun. 30, 2024 shares | Mar. 31, 2024 shares | Mar. 31, 2023 shares | Mar. 31, 2022 shares | Dec. 31, 2024 USD ($) TIME shares | Dec. 31, 2023 USD ($) shares | Dec. 31, 2022 USD ($) shares | Dec. 31, 2021 USD ($) | Mar. 16, 2021 USD ($) shares
Restricted Stock Units (RSUs) [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common Stock Options Restricted Stock Warrants And Changes In Capitalization [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Shares granted in the period |  |  |  |  | 2,300 | 700 | 800 | 344,600 | 390,000 | 641,000 | 355,245 | 396,913 | 650,355 |  |
Share based payment award vesting date |  |  |  |  |  |  |  | Mar. 01, 2029 | Mar. 15, 2028 | Mar. 15, 2027 |  |  |  |  |
Period of service from grant date stock options awarded not subject to forfeiture |  |  |  |  |  |  |  | 2 years | 2 years | 2 years |  |  |  |  |
Restricted stock or unit expense | $ |  |  |  |  |  |  |  |  |  |  | $ 53.8 | $ 43.4 | $ 36.4 |  |
Restricted Stock Units (RSUs) [Member] | Executive Officer [Member] | Minimum [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common Stock Options Restricted Stock Warrants And Changes In Capitalization [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Minimum age of employee with not subject to award forfeiture on condition compliance |  |  |  |  |  |  |  | 55 years | 55 years | 55 years |  |  |  |  |
Unvested Restricted Stock [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common Stock Options Restricted Stock Warrants And Changes In Capitalization [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total intrinsic value | $ |  |  |  |  | $ 548.9 |  |  |  |  |  | 548.9 | 468.5 |  |  |
Equity awards with an aggregate fair value | $ |  |  |  |  |  |  |  |  |  |  | 93.5 | 62.2 |  |  |
Performance Shares [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common Stock Options Restricted Stock Warrants And Changes In Capitalization [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Restricted stock or unit expense | $ |  |  |  |  |  |  |  |  |  |  | 22.0 | 20.0 | 15.2 |  |
Total intrinsic value | $ |  |  |  |  | $ 93.0 |  |  |  |  |  | 93.0 | 75.2 |  |  |
Equity awards with an aggregate fair value | $ |  |  |  |  |  |  |  |  |  |  | $ 31.6 | $ 28.9 | 21.8 |  |
Performance share awards approved, Fair value | $ | $ 14.2 | $ 10.3 |  | $ 8.6 |  |  |  |  |  |  |  |  |  |  |
Vesting period, years | 3 years | 3 years |  | 3 years |  |  |  |  |  |  |  |  |  |  |
2017 Performance Share Awards [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common Stock Options Restricted Stock Warrants And Changes In Capitalization [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Provisional awards, terms |  |  |  |  |  |  |  |  |  |  | The 2024, 2023 and 2022 awards are subject to a three-year performance period that began on January 1, 2024, 2023 and 2022, respectively, and vest on the three-year anniversary of the date of grant (March 1, 2027, March 15, 2026 and March 15, 2025). |  |  |  |
Cash Awards [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common Stock Options Restricted Stock Warrants And Changes In Capitalization [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Shares granted in the period |  |  |  |  |  |  |  |  |  |  | 0 | 0 |  |  |
Cash Awards [Member] | Officer and Key Employees [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common Stock Options Restricted Stock Warrants And Changes In Capitalization [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Provisional awards, terms |  |  |  |  |  |  |  |  |  |  | The ultimate award value will be equal to the trailing twelve‑month price of our common stock, multiplied by the number of units subject to the award, but limited to between 0.5 and 1.5 times the original value of the units determined as of the grant date. |  |  |  |
Vesting period, years |  |  |  |  |  |  |  |  |  |  | 3 years |  |  |  |
Provisional compensation cash awards approved for future grant by compensation committee, value | $ |  |  |  | $ 19.9 |  |  |  |  |  |  |  |  |  |  | $ 18.8
Provisional compensation cash award approved for future grant by compensation committee, units |  |  |  | 125,000 |  |  |  |  |  |  |  |  |  |  | 147,000
Performance awards period, years |  |  |  |  |  |  |  |  |  |  | 1 year |  |  |  |
Ultimate award value, multiples of original value of the units, minimum | TIME |  |  |  |  |  |  |  |  |  |  | 0.5 |  |  |  |
Ultimate award value, multiples of original value of the units, maximum | TIME |  |  |  |  |  |  |  |  |  |  | 1.5 |  |  |  |
2022 Provisional Cash Awards [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common Stock Options Restricted Stock Warrants And Changes In Capitalization [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Cash-based compensation awards, expenses | $ |  |  |  |  |  |  |  |  |  |  | $ 13.2 | $ 13.4 | 0.0 |  |
Performance awards expiration date |  |  |  |  |  |  |  |  |  |  | Jan. 01, 2025 |  |  |  |
2022 Provisional Cash Awards [Member] | Officer and Key Employees [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common Stock Options Restricted Stock Warrants And Changes In Capitalization [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Provisional compensation cash award approved for future grant by compensation committee, units |  |  |  |  |  |  |  |  | 122,000 |  |  |  |  |  |
2021 Provisional Cash Awards [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common Stock Options Restricted Stock Warrants And Changes In Capitalization [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Provisional compensation cash award approved for future grant by compensation committee, units |  |  |  |  | 129,000 |  |  |  |  |  | 129,000 |  |  |  |
Cash-based compensation awards, expenses | $ |  |  |  |  |  |  |  |  |  |  |  | $ 13.1 | $ 12.4 | $ 0.0 |
Performance awards expiration date |  |  |  |  |  |  |  |  |  |  | Jan. 01, 2024 |  |  |  |
Cash award with aggregate fair value vested and distributed to participants | $ |  |  |  |  |  |  |  |  |  |  | $ 25.4 |  |  |  |
2021 Provisional Cash Awards [Member] | Officer and Key Employees [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common Stock Options Restricted Stock Warrants And Changes In Capitalization [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Provisional compensation cash award approved for future grant by compensation committee, units |  |  |  |  |  |  |  |  |  | 143,000 |  |  |  |  |
2020 Provisional Cash Awards [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common Stock Options Restricted Stock Warrants And Changes In Capitalization [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Provisional compensation cash award approved for future grant by compensation committee, units |  |  |  |  |  |  |  |  |  |  |  | 191,000 |  |  |
Cash award with aggregate fair value vested and distributed to participants | $ |  |  |  |  |  |  |  |  |  |  |  | $ 24.7 |  |  |
2019 Provisional Cash Awards [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common Stock Options Restricted Stock Warrants And Changes In Capitalization [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Provisional compensation cash award approved for future grant by compensation committee, units |  |  |  |  |  |  |  |  |  |  |  |  | 177,000 |  |
Cash award with aggregate fair value vested and distributed to participants | $ |  |  |  |  |  |  |  |  |  |  |  |  | $ 21.1 |  |
Long Term Incentive Plan [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common Stock Options Restricted Stock Warrants And Changes In Capitalization [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Shares available for grant |  |  |  |  | 11,100,000 |  |  |  |  |  | 11,100,000 |  |  |  |
Shares granted in the period |  |  | 3,500,000 |  |  |  |  |  |  |  | 2,500,000 |  |  |  |
Long Term Incentive Plan [Member] | Officer and Key Employees [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common Stock Options Restricted Stock Warrants And Changes In Capitalization [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Shares available for grant | 1,044,000 | 1,131,000 |  |  |  |  |  |  |  |  |  |  |  |  |
Long Term Incentive Plan [Member] | Restricted Stock, Restricted Stock Units and Performance Unit Awards [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common Stock Options Restricted Stock Warrants And Changes In Capitalization [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Shares authorized |  |  |  |  | 4,000,000 |  |  |  |  |  | 4,000,000 |  |  |  |
Shares available for grant |  |  |  |  | 2,500,000 |  |  |  |  |  | 2,500,000 |  |  |  |
Long Term Incentive Plan [Member] | Restricted Stock Units (RSUs) [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common Stock Options Restricted Stock Warrants And Changes In Capitalization [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Shares granted in the period |  |  |  |  |  |  |  |  |  |  | 355,245 | 396,913 | 650,355 |  |
Fair value of grants in period | $ |  |  |  |  |  |  |  |  |  |  | $ 85.1 | $ 67.0 | $ 99.4 |  |
Long Term Incentive Plan [Member] | Performance Shares [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common Stock Options Restricted Stock Warrants And Changes In Capitalization [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Shares authorized | 58,000 | 58,000 |  | 54,000 |  |  |  |  |  |  |  |  |  |  |
Long Term Incentive Plan [Member] | Performance Shares [Member] | Executive Officer [Member] | Minimum [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common Stock Options Restricted Stock Warrants And Changes In Capitalization [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Minimum age of employee with not subject to award forfeiture on condition compliance | 62 years | 55 years |  | 55 years |  |  |  |  |  |  |  |  |  |  |
Period of service from grant date stock options awarded not subject to forfeiture |  | 2 years |  | 2 years |  |  |  |  |  |  |  |  |  |  |

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