Leases - Components of lease expense (Details) - USD ($) $ in Millions |
3 Months Ended | 6 Months Ended |
|---|---|---|
Jun. 30, 2019 |
Jun. 30, 2019 |
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| Finance lease cost | ||
| Depreciation of leased assets | $ 16 | $ 18 |
| Interest on lease liabilities | 2 | 3 |
| Total finance lease cost | 18 | 21 |
| Operating lease cost | 25 | 44 |
| Sublease income | (1) | (2) |
| Total lease cost | $ 42 | $ 63 |
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- Definition The amount of total finance lease cost. 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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- References No definition available.
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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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- 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 sublease income excluding finance and operating lease expense. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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