Leases - Summary of Components of Lease Expense (Detail) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Finance lease cost:
Net lease cost	$ 122.0	$ 130.5	$ 117.4
Other Operating Income (Expense)
Lessee Lease Description [Line Items]
Operating lease cost	89.0	93.1	86.4
Finance lease cost:
Variable lease cost	31.8	34.2	30.6
Short-term lease cost	2.1	2.6	1.6
Depreciation And Amortization
Finance lease cost:
Amortization of lease assets	1.7	1.7	1.6
Interest
Finance lease cost:
Interest of lease liabilities	0.1	0.1	0.1
Information And Other
Finance lease cost:
Sublease income	$ (2.7)	$ (1.2)	$ (2.9)

Interest of lease liabilities.

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- Definition

Amount of amortization expense attributable to right-of-use asset from finance lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 53
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479589/842-20-55-53

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
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-Name Accounting Standards Codification
-Section 45
-Paragraph 4
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-Publisher FASB
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147478964/842-20-50-4

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- Definition

Amount of lease cost recognized by lessee for lease contract.

+ References

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- References

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147478964/842-20-50-3

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- Definition

Amount of single lease cost, calculated by allocation of remaining cost of lease over remaining lease term. Includes, but is not limited to, single lease cost, after impairment of right-of-use asset, calculated by amortization of remaining right-of-use asset and accretion of lease liability.

+ References

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- Definition

Amount of short-term lease cost, excluding expense for lease with term of one month or less.

+ References

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- Definition

Amount of sublease income excluding finance and operating lease expense.

+ References

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- Definition

Amount of variable lease cost, excluded from lease liability, recognized when obligation for payment is incurred for finance and operating leases.

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