Leases - Components of Lease Costs (Detail) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Leases [Abstract]
Operating lease cost	$ 200	$ 414
Finance lease cost: Amortization of leased assets	31	43
Finance lease cost: Interest on lease obligations	20	21
Short-term lease cost	199	164
Variable lease cost	38	89
Sublease income	(15)	(12)
Total lease cost	$ 473	$ 719
Total rental expense			$ 154
Income from subleases			$ 8

Amount of interest paid on finance lease liability.

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- Definition

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
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- Definition

Amount of rent expense incurred for leased assets, including but not limited to, furniture and equipment, that is not directly or indirectly associated with the manufacture, sale or creation of a product or product line.

+ References

No definition available.

+ Details

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- Definition

Amount of lease cost recognized by lessee for lease contract.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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- References

No definition available.

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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

The amount of revenue recognized for the period under subleasing arrangements.

+ References

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- Definition

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

+ References

+ Details

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- Definition

Amount of sublease income excluding finance and operating lease expense.

+ References

+ Details

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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.

+ References

+ Details

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