Leases - Cash Flow From Lease Transactions (Details) - USD ($) $ in Millions |
12 Months Ended | |
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Dec. 31, 2020 |
Dec. 31, 2019 |
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| Cash paid for amounts included in the measurement of lease liabilities | ||
| Operating cash outflows from finance leases | $ 10 | $ 8 |
| Financing cash outflows from finance leases | 85 | 22 |
| Operating cash outflows from operating leases | 1,566 | 1,541 |
| ROU assets obtained in exchange for new finance lease liabilities | 176 | 209 |
| ROU assets obtained in exchange for new operating lease liabilities | $ 1,130 | 6,481 |
| ROU assets obtained in exchange for new operating lease liabilities - post adoption | $ 1,679 | |
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- References No definition available.
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- Definition Gross amount of lessee's right to use underlying asset under finance lease. No definition available.
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- Definition Gross amount of lessee's right to use underlying asset under operating lease. 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 operating lease liability. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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