Leases (Future Minimum Lease Payments Under Non-Cancellable Leases) (Details) $ in Millions	Mar. 31, 2020 USD ($)
Leases [Abstract]
Operating Leases, 2020 (excluding the three months ended March 31, 2020)	$ 20
Operating Leases, 2021	23
Operating Leases, 2022	20
Operating Leases, 2023	15
Operating Leases, 2024	11
Operating Leases, Thereafter	85
Operating Leases, Total future minimum lease payments	174
Finance Leases, 2020 (excluding the three months ended March 31, 2020)	27
Finance Leases, 2021	29
Finance Leases, 2022	19
Finance Leases, 2023	12
Finance Leases, 2024	5
Finance Leases, Thereafter	1
Finance Leases, Total future minimum lease payments	$ 92

Amount of lessee's undiscounted obligation for lease payments for finance lease.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918701-209980

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- Definition

Amount of lessee's undiscounted obligation for lease payments for finance lease, due after fifth fiscal year following latest fiscal year.

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Amount of lessee's undiscounted obligation for lease payments for finance lease, due in next fiscal year following latest fiscal year.

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Amount of lessee's undiscounted obligation for lease payments for finance lease, due in fourth fiscal year following latest fiscal year.

+ References

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- Definition

Amount of lessee's undiscounted obligation for lease payments for finance lease, due in third fiscal year following latest fiscal year.

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- Definition

Amount of lessee's undiscounted obligation for lease payments for finance lease, due in second fiscal year following latest fiscal year.

+ References

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- Definition

Amount of lessee's undiscounted obligation for lease payments for finance lease, due in remainder of fiscal year following latest fiscal year ended.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918701-209980

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- References

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- Definition

Amount of lessee's undiscounted obligation for lease payments for operating lease.

+ References

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Amount of lessee's undiscounted obligation for lease payments for operating lease, due after fifth fiscal year following latest fiscal year.

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Amount of lessee's undiscounted obligation for lease payments for operating lease, due in next fiscal year following latest fiscal year.

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Amount of lessee's undiscounted obligation for lease payments for operating lease, due in fourth fiscal year following latest fiscal year.

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Amount of lessee's undiscounted obligation for lease payments for operating lease, due in third fiscal year following latest fiscal year.

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Amount of lessee's undiscounted obligation for lease payments for operating lease, due in second fiscal year following latest fiscal year.

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Amount of lessee's undiscounted obligation for lease payments for operating lease having an initial or remaining lease term in excess of one year due in remainder of fiscal year following latest fiscal year.

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