Long-Term Debt And Lease Obligation (Lease Payments Over Next Five Years) (Details) $ in Millions	12 Months Ended
Dec. 31, 2020 USD ($)
Long-term Debt and Lease Obligation [Abstract]
Finance Lease 2021	$ 15
Finance Lease 2022	12
Finance Lease 2023	10
Finance Lease 2024	6
Finance Lease 2025	4
Finance Lease 2026 and thereafter	2
Operating Leases 2021	2
Operating Leases 2022	2
Operating Leases 2023	2
Operating Leases 2024	2
Operating Leases 2025	1
Operating Leases 2026 and thereafter	2
Total Finance and Operating Lease 2021	17
Total Finance and Operating Lease 2022	14
Total Finance and Operating Lease 2023	12
Total Finance and Operating Lease 2024	8
Total Finance and Operating Lease 2025	5
Total Finance and Operating Lease 2026 and thereafter	$ 4

Total Finance and Operating Lease Obligations Due After Year Five

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- Definition

Total Finance and Operating Lease Obligations Due Next Twelve Months

+ References

No definition available.

+ Details

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- Definition

Total Finance and Operating Lease Obligations Due Year Five

+ References

No definition available.

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- Definition

Total Finance and Operating Lease Obligations Due Year Four

+ References

No definition available.

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- Definition

Total Finance and Operating Lease Obligations Due Year Three

+ References

No definition available.

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- Definition

Total Finance and Operating Lease Obligations Due Year Two

+ References

No definition available.

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- Definition

Amount of lessee's undiscounted obligation for lease payment for finance lease to be paid after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ 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=121609121&loc=SL77918701-209980

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- Definition

Amount of lessee's undiscounted obligation for lease payment for finance lease to be paid in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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- Definition

Amount of lessee's undiscounted obligation for lease payment for finance lease to be paid in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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- Definition

Amount of lessee's undiscounted obligation for lease payment for finance lease to be paid in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

+ Details

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- Definition

Amount of lessee's undiscounted obligation for lease payment for finance lease to be paid in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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- Definition

Amount of lessee's undiscounted obligation for lease payment for finance lease to be paid in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

+ Details

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- Definition

Amount of lessee's undiscounted obligation for lease payment for operating lease due after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

+ Details

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- Definition

Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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- Definition

Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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- Definition

Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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- Definition

Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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- Definition

Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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No definition available.

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