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Restricted Stock, Performance Share and Cash Awards - Additional Information (Detail) $ in Millions |  |  |  | 3 Months Ended | 6 Months Ended |  |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Mar. 15, 2023 USD ($) shares | May 10, 2022 shares | Mar. 15, 2022 USD ($) shares | Jun. 30, 2023 USD ($) shares | Mar. 31, 2023 USD ($) shares | Jun. 30, 2022 USD ($) shares | Mar. 31, 2022 USD ($) shares | Jun. 30, 2023 USD ($) TIME shares | Jun. 30, 2022 USD ($) shares | Dec. 31, 2022 shares | Mar. 31, 2021 shares | Mar. 16, 2021 USD ($) shares | Mar. 12, 2020 USD ($) shares
Common Stock Options Restricted Stock Warrants And Changes In Capitalization [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based compensation, shares outstanding | shares |  |  |  | 8,400,000 |  |  |  | 8,400,000 |  | 8,300,000 |  |  |
Officer and Key Employees [Member] |  |  |  |  |  |  |  |  |  |  |  |  |
Common Stock Options Restricted Stock Warrants And Changes In Capitalization [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Performance awards period, years |  |  |  |  |  |  |  | 1 year |  |  |  |  |
Restricted Stock Units (RSUs) [Member] |  |  |  |  |  |  |  |  |  |  |  |  |
Common Stock Options Restricted Stock Warrants And Changes In Capitalization [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Period of service from grant date stock options awarded not subject to forfeiture |  |  |  |  | 2 years |  | 2 years |  |  |  |  |  |
Restricted stock or unit expense |  |  |  | $ 11.0 |  | $ 10.1 |  | $ 20.7 | $ 17.7 |  |  |  |
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 |  |  |  |  |  |
Restricted Stock Units (RSUs) [Member] | Tranche One [Member] |  |  |  |  |  |  |  |  |  |  |  |  |
Common Stock Options Restricted Stock Warrants And Changes In Capitalization [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Shares granted in the period | shares |  |  |  |  | 378,000 |  | 295,000 |  |  |  |  |  |
Fair value of grants in period |  |  |  |  | $ 67.0 |  | $ 46.8 |  |  |  |  |  |
Share based payment award vesting date |  |  |  |  | Mar. 15, 2028 |  | Mar. 15, 2027 |  |  |  |  |  |
Restricted Stock Units (RSUs) [Member] | Tranche Two [Member] |  |  |  |  |  |  |  |  |  |  |  |  |
Common Stock Options Restricted Stock Warrants And Changes In Capitalization [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Shares granted in the period | shares |  |  |  |  |  |  | 335,000 |  |  |  |  |  |
Fair value of grants in period |  |  |  |  |  |  | $ 52.6 |  |  |  |  |  |
Share based payment award vesting date |  |  |  |  |  |  | Feb. 01, 2027 |  |  |  |  |  |
Unvested Restricted Stock [Member] |  |  |  |  |  |  |  |  |  |  |  |  |
Common Stock Options Restricted Stock Warrants And Changes In Capitalization [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Total intrinsic value |  |  |  | 460.5 |  | 353.1 |  | 460.5 | 353.1 |  |  |  |
Equity awards with an aggregate fair value |  |  |  |  |  |  |  | 62.0 | 62.0 |  |  |  |
Performance Shares [Member] |  |  |  |  |  |  |  |  |  |  |  |  |
Common Stock Options Restricted Stock Warrants And Changes In Capitalization [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Restricted stock or unit expense |  |  |  | 3.8 |  | 3.7 |  | 8.5 | 7.5 |  |  |  |
Total intrinsic value |  |  |  | 64.3 |  | 54.2 |  | 64.3 | 54.2 |  |  |  |
Equity awards with an aggregate fair value |  |  |  |  |  |  |  | $ 28.9 | 21.8 |  |  |  |
Performance share awards approved, Fair value | $ 10.3 |  | $ 8.6 |  |  |  |  |  |  |  |  |  |
Vesting period, years |  |  |  |  | 2 years |  |  |  |  |  |  |  |
2017 Performance Share Awards [Member] |  |  |  |  |  |  |  |  |  |  |  |  |
Common Stock Options Restricted Stock Warrants And Changes In Capitalization [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Provisional awards, terms |  |  |  |  |  |  |  | The 2023 and 2022 awards are subject to a three-year performance period that began on January 1, 2023 and 2022, respectively, and vest on the three-year anniversary of the date of grant (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 | shares |  |  |  |  |  |  |  | 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 | shares |  |  | 125,000 |  |  |  | 143,000 |  |  |  | 208,000 | 147,000 |
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 |  |  |  |  |
2023 Provisional Cash Awards [Member] |  |  |  |  |  |  |  |  |  |  |  |  |
Common Stock Options Restricted Stock Warrants And Changes In Capitalization [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Cash-based compensation awards, expenses |  |  |  | 3.1 |  |  |  | $ 5.7 |  |  |  |  |
2021 Provisional Cash Awards [Member] |  |  |  |  |  |  |  |  |  |  |  |  |
Common Stock Options Restricted Stock Warrants And Changes In Capitalization [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Cash-based compensation awards, expenses |  |  |  | $ 3.2 |  |  |  | $ 6.5 |  |  |  |  |
Performance awards expiration date |  |  |  |  |  |  |  | Jan. 01, 2024 |  |  |  |  |
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 | shares |  |  |  | 191,000 |  |  |  | 191,000 |  |  |  |  |
Cash-based compensation awards, expenses |  |  |  | $ 0.1 |  | $ 2.9 |  | $ 0.1 | $ 6.0 |  |  |  |
Cash award with aggregate fair value vested and distributed to participants |  |  |  |  |  |  |  | $ 24.7 |  |  |  |  |
Performance awards expiration date |  |  |  |  |  |  |  | Jan. 01, 2023 |  |  |  |  |
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 | shares |  |  |  |  |  | 177,000 |  |  | 177,000 |  |  |  |
Cash award with aggregate fair value vested and distributed to participants |  |  |  |  |  |  |  |  | $ 21.1 |  |  |  |
2019 Provisional Cash Awards [Member] | Officer and Key Employees [Member] |  |  |  |  |  |  |  |  |  |  |  |  |
Common Stock Options Restricted Stock Warrants And Changes In Capitalization [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Provisional compensation cash awards approved for future grant by compensation committee, value |  |  |  |  |  |  |  |  |  |  |  |  | $ 18.4
Provisional compensation cash award approved for future grant by compensation committee, units | shares |  |  |  |  |  |  |  |  |  |  |  |  | 213,000
Long Term Incentive Plan [Member] |  |  |  |  |  |  |  |  |  |  |  |  |
Common Stock Options Restricted Stock Warrants And Changes In Capitalization [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based compensation, shares outstanding, Value |  |  |  | $ 4.0 |  |  |  | $ 4.0 |  |  |  |  |
Shares granted in the period | shares |  | 3,500,000 |  |  |  |  |  | 2,800,000 |  |  |  |  |
Long Term Incentive Plan [Member] | Performance Shares [Member] |  |  |  |  |  |  |  |  |  |  |  |  |
Common Stock Options Restricted Stock Warrants And Changes In Capitalization [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Shares authorized | shares | 58,000 |  |  |  |  |  |  |  |  |  |  |  |
2017 Long Term Incentive Plan [Member] | Minimum [Member] |  |  |  |  |  |  |  |  |  |  |  |  |
Common Stock Options Restricted Stock Warrants And Changes In Capitalization [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Period of service from grant date stock options awarded not subject to forfeiture |  |  |  |  |  |  |  | 2 years | 2 years |  |  |  |
2017 Long Term Incentive Plan [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 |  |  |  |
2017 Long Term Incentive Plan [Member] | Performance Shares [Member] |  |  |  |  |  |  |  |  |  |  |  |  |
Common Stock Options Restricted Stock Warrants And Changes In Capitalization [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Shares authorized | shares |  |  | 54,000 |  |  |  |  |  |  |  |  |  |

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