Leases - Summary of Components of Lease Expense (Detail) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Finance lease cost:
Net lease cost	$ 118	$ 121	$ 120
Other Operating Income (Expense)
Lessee Lease Description [Line Items]
Operating lease cost	86	89	88
Finance lease cost:
Variable lease cost	31	32	31
Short-term lease cost	2	1	1
Depreciation And Amortization
Finance lease cost:
Amortization of lease assets	2	2	2
Information And Other
Finance lease cost:
Sublease income	$ (3)	$ (3)	$ (2)

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

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Amount of lease cost recognized by lessee for lease contract.

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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.

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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.

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

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Amount of sublease income excluding finance and operating lease expense.

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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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