Share-Based Compensation Plans - Total Compensation Expense for Share-Based Payment Arrangements to Employees (Detail) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total Share-Based Compensation Expense	$ 125.2	$ 95.5	$ 91.4
Tax Benefits Recognized	31.4	24.0	22.9
Restricted Stock Unit Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total Share-Based Compensation Expense	96.4	78.2	78.1
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total Share-Based Compensation Expense	0.0	0.0	0.5
Performance Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total Share-Based Compensation Expense	$ 28.8	$ 17.3	$ 12.8

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

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Amount of tax benefit for recognition of expense of award under share-based payment arrangement.

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