Leasing - Supplemental Cash Flow Information (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2019
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows from operating leases	$ 38	$ 70
Operating cash flows from finance leases	0	0
Financing cash flows from finance leases	0	0
Lease Assets Obtained in Exchange for Lease Obligations
Operating Leases	8	20
Finance Leases	$ 8	$ 9

Cash Flow, Lessee

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- Definition

Right-of-Use Asset Obtained in Exchange for Lease Liability

+ References

No definition available.

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- Definition

Amount of interest paid on finance lease liability.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (g)(1)
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+ Details

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- Definition

Amount of cash outflow for principal payment on finance lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
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- Definition

Amount of cash outflow from operating lease, excluding payments to bring another asset to condition and location necessary for its intended use.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 20
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-Paragraph 5
-Subparagraph (c)
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- Definition

Amount of increase in right-of-use asset obtained in exchange for finance lease liability.

+ References

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- Definition

Amount of increase in right-of-use asset obtained in exchange for operating lease liability.

+ References

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