Fresh Start Accounting (Narrative) (Details) $ in Millions	Sep. 30, 2021 USD ($)
Fresh-Start Adjustment [Line Items]
Decrease in right-of-use related to unfavorable lease contracts	$ 4
Reduction in deferred tax assets	1,500
Successor [Member]
Fresh-Start Adjustment [Line Items]
Enterprise value	12,500
Successor [Member] \| Minimum [Member]
Fresh-Start Adjustment [Line Items]
Enterprise value	10,500
Successor [Member] \| Maximum [Member]
Fresh-Start Adjustment [Line Items]
Enterprise value	$ 12,500

Fresh-Start Adjustment, Increase (Decrease), Deferred Tax Assets, Gross

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- Definition

Fresh-Start Adjustment, Increase (Decrease), Operating Leases Right Of Use Assets

+ References

No definition available.

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Amount of reorganization value related to present value of discounted cash flows of the emerging entity. Reorganization value is the amount attributed to the reconstituted entity, as well as the expected net realizable value of those assets that will be disposed before reconstitution occurs.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 852
-SubTopic 10
-Section 55
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=84165509&loc=d3e56239-112766

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 852
-SubTopic 10
-Section 05
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=49179835&loc=d3e54813-112758

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