Long-Term Debt And Lease Obligation (Lease Payments Over Next Five Years) (Details) $ in Millions	12 Months Ended
Dec. 31, 2019 USD ($)
Long-term Debt and Lease Obligation [Abstract]
Finance Lease 2020	$ 14
Finance Lease 2021	10
Finance Lease 2022	8
Finance Lease 2023	6
Finance Lease 2024	3
Finance Lease After 2025	1
Operating Leases 2020	5
Operating Leases 2021	2
Operating Leases 2022	2
Operating Leases 2023	2
Operating Leases 2024	1
Operating Leases After 2025	3
Total Finance and Operating Lease 2020	19
Total Finance and Operating Lease 2021	12
Total Finance and Operating Lease 2022	10
Total Finance and Operating Lease 2023	8
Total Finance and Operating Lease 2024	4
Total Finance and Operating Lease After 2025	$ 4

Total Finance and Operating Lease Obligations Due After Year Five

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Total Finance and Operating Lease Obligations Due Next Twelve Months

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Total Finance and Operating Lease Obligations Due Year Five

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Total Finance and Operating Lease Obligations Due Year Four

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Total Finance and Operating Lease Obligations Due Year Three

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Total Finance and Operating Lease Obligations Due Year Two

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

+ 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 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 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 fourth fiscal year following latest fiscal year.

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

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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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