Restructuring Costs And Other Charges (Changes In Restructuring Reserve) (Details) - USD ($) $ in Millions	4 Months Ended	5 Months Ended
Apr. 30, 2021	Sep. 30, 2021
Successor [Member]
Restructuring Reserve, Beginning Balance		$ 7
Severance expense		6
Other costs		13
Cash payments during the period		(18)
Restructuring Reserve, Ending Balance	$ 7	8
Predecessor [Member]
Restructuring Reserve, Beginning Balance	2	$ 7
Severance expense	7
Cash payments during the period	(2)
Restructuring Reserve, Ending Balance	$ 7

Amount of other expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses associated with a discontinued operation or an asset retirement obligation.

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-Publisher FASB
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3602-108585

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Balance Type:	debit
Period Type:	duration

- Definition

Amount of cash payments made as the result of exit or disposal activities. Excludes payments associated with a discontinued operation or an asset retirement obligation.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)(2)
-URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 17
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3367-108585

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- Definition

Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section 50
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-Topic 420
-SubTopic 10
-Section S99
-Paragraph 2
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-URI http://asc.fasb.org/extlink&oid=115931487&loc=d3e140904-122747

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Balance Type:	credit
Period Type:	instant

- Definition

Amount of expenses for special or contractual termination benefits provided to current employees involuntarily terminated under a benefit arrangement associated exit or disposal activities pursuant to an authorized plan. Excludes expenses related to one-time termination benefits, a discontinued operation or an asset retirement obligation.

+ References

+ Details

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Balance Type:	debit
Period Type:	duration

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Namespace Prefix:
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Balance Type:
Period Type:

- Details

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Balance Type:
Period Type: