Other Assets - Schedule of Other Assets (Detail) - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020
Other Assets [Abstract]
Finance Lease, Right-of-Use Asset	$ 9	$ 8
Deferred income taxes	102	197
Overfunded pension plans	110	101
Cash surrender value of life insurance contracts	49	49
Other	227	63
Total	$ 497	$ 418

Carrying amount as of the balance sheet date of amounts which could be received based on the terms of the insurance contract upon surrendering life policies owned by the entity.

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Amount after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and other tax receivables expected to be realized or consumed within one year or operating cycle, if longer.

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Amount of asset, recognized in statement of financial position, for overfunded defined benefit pension and other postretirement plans.

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Amount of lessee's right to use underlying asset under finance lease.

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Amount of other miscellaneous assets expected to be realized or consumed after one year or normal operating cycle, if longer.

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