Leases - Components of lease expense (Details) - USD ($) $ in Millions |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2020 |
Dec. 31, 2019 |
Dec. 31, 2018 |
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| Finance lease cost | Ìý | Ìý | Ìý |
| Depreciation of leased assets | $ 35 | $ 37 | Ìý |
| Interest on lease liabilities | 6 | 6 | Ìý |
| Total finance lease cost | 41 | 43 | Ìý |
| Operating lease cost | 93 | 89 | Ìý |
| Sublease income | (2) | (3) | Ìý |
| Total lease cost | $ 132 | $ 129 | Ìý |
| Rent expense | Ìý | Ìý | $ 64 |
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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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