Leases - Supplemental Cash Flow Information related to Leases (Detail) - USD ($) $ in Millions |
12 Months Ended | ||
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Dec. 31, 2020 |
Dec. 31, 2019 |
Dec. 31, 2018 |
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| Cash paid for amounts included in the measurement of lease liabilities: | |||
| Operating cash outflows from operating leases | $ 456 | $ 396 | |
| Operating cash outflows from finance leases (interest payments) | 100 | 104 | |
| Financing cash outflows from finance leases | 338 | 321 | $ 181 |
| Leased assets obtained in exchange for finance lease liabilities | 188 | 616 | |
| Leased assets obtained in exchange for operating lease liabilities | $ 553 | $ 202 | |
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- Definition Cash paid for amounts included in measurement of lease liabilities. No definition available.
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- Definition Amount of interest paid on finance lease liability. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of cash outflow for principal payment on finance lease. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of cash outflow from operating lease, excluding payments to bring another asset to condition and location necessary for its intended use. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of increase in right-of-use asset obtained in exchange for finance lease liability. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of increase in right-of-use asset obtained in exchange for operating lease liability. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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