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Share-Based Compensation - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions |  | 9 Months Ended
--- | --- | ---
May 01, 2025 | Sep. 30, 2025 | Sep. 30, 2024
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Share-based Payment Arrangement, Shares Withheld for Tax Withholding Obligation |  | 8,000 | 14,000
Payment, Tax Withholding, Share-based Payment Arrangement |  | $ 1.0 | $ 1.5
Unrecognized compensation cost |  | 7.7 |
Awards to non-employee directors [Member] |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value | $ 134.05 |  |
Granted awards (shares) | 1,000 |  |
Unrecognized compensation expense related to the awards to non-employee directors |  | $ 0.6 |
Shares awarded to non-employee directors [Line Items] |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value | $ 134.05 |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period | 1,000 |  |
Award to key employees [Member] |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Expired In Period |  | (26,000) |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value |  | $ 125.56 |
Granted awards (shares) |  | 99,000 |
Vesting period |  | 3 years |
Payment, Tax Withholding, Share-based Payment Arrangement |  | $ 1.0 |
Intrinsic value of the SICP awards |  | $ 39.0 |
Shares awarded to non-employee directors [Line Items] |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value |  | $ 125.56 |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period |  | 99,000 |
Accelerated Vested Shares [Member] |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Share-based Payment Arrangement, Shares Withheld for Tax Withholding Obligation |  | 8,000 |

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- Definition Amount of cost not yet recognized for nonvested award under share-based payment arrangement. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 718 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (i) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480429/718-10-50-2 + Details
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- Definition Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 718 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (i) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480429/718-10-50-2 + Details
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- Definition The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 718 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (c)(2)(iii)(01) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480429/718-10-50-2 + Details
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- Definition The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 718 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (c)(2)(iii)(01) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480429/718-10-50-2 + Details
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