Leases - Lease Related Assets and Liabilities (Details) - USD ($) $ in Millions |
Mar. 31, 2019 |
Dec. 31, 2018 |
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| Leases [Abstract] | ||
| Operating lease assets | $ 12 | |
| Finance lease assets | 41 | $ 41 |
| Total lease assets | 53 | |
| Operating lease liabilities, current | 4 | |
| Finance lease liabilities, current | 5 | |
| Operating lease liabilities, noncurrent | 8 | |
| Finance lease liabilities, noncurrent | 59 | $ 59 |
| Total lease liabilities | $ 76 |
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- Definition Present value of lessee's discounted obligation for lease payments from finance lease, classified as current. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Present value of lessee's discounted obligation for lease payments from finance lease, classified as noncurrent. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of lessee's right to use underlying asset under finance lease. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- References No definition available.
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- Definition Present value of lessee's discounted obligation for lease payments from operating lease, classified as current. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Present value of lessee's discounted obligation for lease payments from operating lease, classified as noncurrent. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of lessee's right to use underlying asset under operating lease. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Lease, Liability No definition available.
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- Definition Lease, Right-Of-Use Asset No definition available.
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