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Other Commitments And Contingencies Other Commitments and Contingencies (Insurance Recoveries and Cash Collected (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended	16 Months Ended	25 Months Ended
	Sep. 30, 2020	Sep. 30, 2020	Dec. 31, 2019	Sep. 30, 2020
Commitments and Contingencies Disclosure [Abstract]
Insurance recoveries recorded	$ 0	$ 0	$ 800	$ 800
Cash collected from insurance recoveries				$ (800)

X

- Definition

Proceeds From Insurance Settlement

+ References

No definition available.

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- References

No definition available.

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- Definition

The amount recovered from insurance. These recoveries reduce costs and losses that are reported as a separate line item under operating expenses.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.3)
-URI http://asc.fasb.org/extlink&oid=120395209&loc=SL114868664-224227

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