Leases - Supplemental Balance Sheet (Details) - USD ($) $ in Millions	Sep. 30, 2019	Dec. 31, 2018
Assets
Operating lease assets	$ 117	$ 0
Finance lease assets	16
Total leased assets	133
Current
Operating	29
Finance	7
Noncurrent
Operating	90	$ 0
Finance	5
Total lease liabilities	$ 131
Weighted-average remaining lease term (years)
Operating leases	5 years 4 months 24 days
Finance leases	4 years 10 months 24 days
Weighted-average discount rate
Operating leases	6.71%
Finance leases	5.26%

Lease, Liability

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Lease, Right-of-Use Asset

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- Definition

Leases, Weighted Average Discount Rate [Abstract]

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- Definition

Present value of lessee's discounted obligation for lease payments from finance lease, classified as current.

+ References

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-Name Accounting Standards Codification
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Present value of lessee's discounted obligation for lease payments from finance lease, classified as noncurrent.

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Amount of lessee's right to use underlying asset under finance lease.

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Weighted average discount rate for finance lease calculated at point in time.

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Weighted average remaining lease term for finance lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of lessee's right to use underlying asset under operating lease.

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