Leases - Schedule of Components of Lease Expense (Detail) - USD ($) $ in Millions |
12 Months Ended | |
|---|---|---|
Dec. 31, 2020 |
Dec. 31, 2019 |
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| Operating leases: | ||
| Operating lease expense | $ 451 | $ 426 |
| Finance leases: | ||
| Amortization of leased assets | 348 | 299 |
| Interest on lease liabilities | 100 | 104 |
| Total finance lease expense | 448 | 403 |
| Total lease expense | $ 899 | $ 829 |
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- Definition Financing lease expense. No definition available.
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- Definition Amount of interest expense on finance lease liability. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of amortization expense attributable to right-of-use asset from finance lease. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of lease cost recognized by lessee for lease contract. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- References No definition available.
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- References No definition available.
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- Definition Amount of operating lease expense. Excludes sublease income. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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