Leases - Supplemental Balance Sheet Information (Details) $ in Millions	Dec. 31, 2019 USD ($)
Assets
Operating lease assets	$ 1,060
Finance lease assets	154
Total leased assets	1,214
Current
Operating	249
Finance	11
Noncurrent
Operating	854
Finance	160
Total lease liabilities	$ 1,274
Weighted-average remaining lease term (years)
Operating leases	7 years 6 months
Finance leases	13 years 1 month 6 days
Weighted-average discount rate
Operating leases	6.19%
Finance leases	5.60%

Lease, Liability

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- Definition

Lease, Right-of-Use Asset

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- Definition

Leases, Weighted Average Discount Rate [Abstract]

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- Definition

Weighted Average Remaining Lease Term [Abstract]

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- References

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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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-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
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- Definition

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

+ References

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- Definition

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

+ References

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- Definition

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

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