Leases Leases (Reconciliation of Future Lease Payments to Total Lease Liabilities) (Details) $ in Millions	Dec. 31, 2019 USD ($)
Leases (Reconciliation of Future Lease Payments to Total Lease Liabilities) [Abstract]
Future Minimum Payments, Due 2020	$ 172
Future Minimum Payments, Due 2021	149
Future Minimum Payments, Due 2022	136
Future Minimum Payments, Due 2023	116
Future Minimum Payments, Due 2024	87
Future Minimum Payments, Due Thereafter	135
Total future minimum payments	795
Imputed interest	155
Total lease liabilities	$ 640

Reconciliation of future lease payments to total lease liabilities.

No definition available.

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- Definition

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

+ References

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

+ References

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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.

+ References

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

+ References

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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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- Definition

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

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- Definition

Amount of required minimum rental payments for leases having an initial or remaining non-cancelable letter-terms in excess of one year.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 50
-Paragraph 2
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