Leases - Lease Costs (Details) - USD ($) $ in Millions |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Jun. 30, 2021 |
Jun. 30, 2020 |
Jun. 30, 2021 |
Jun. 30, 2020 |
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| Finance lease cost: | ||||
| Amortization of assets | $ 61 | $ 49 | $ 113 | $ 93 |
| Interest on lease liabilities | 3 | 4 | 7 | 8 |
| Operating Lease, Cost | 74 | 116 | 150 | 211 |
| Short-term lease cost | 1 | 4 | 4 | 10 |
| Variable lease cost | 22 | 32 | 42 | 62 |
| Sublease income | (1) | 0 | (1) | (1) |
| Total lease cost | $ 160 | $ 205 | $ 315 | $ 383 |
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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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- 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. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of short-term lease cost, excluding expense for lease with term of one month or less. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of sublease income excluding finance and operating lease expense. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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