Summary of Components Included in Reorganization Items (Detail) - USD ($) $ in Thousands	4 Months Ended	5 Months Ended
Jul. 31, 2017	Dec. 31, 2017
Reorganizations [Line Items]
Debt, sale leaseback and other reorganization items		$ 1,631
Reorganization-related professional fees		2,668
Loss on reorganization items		$ 4,299
Predecessor
Reorganizations [Line Items]
Gain on settlement of Liabilities subject to compromise	$ (767,640)
Fresh start adjustments	1,820,018
Debt, sale leaseback and other reorganization items	316,504
Reorganization-related professional fees	28,023
Loss on reorganization items	$ 1,396,905

Debt sale leaseback and other reorganization items.

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Gain on settlement of liabilities subject to compromise.

+ References

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- Definition

Reorganizations.

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- Definition

Amount of reorganization items related to legal and advisory professional fees related to entities in bankruptcy.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 852
-SubTopic 10
-Section 45
-Paragraph 9
-URI http://asc.fasb.org/extlink&oid=114872137&loc=d3e55730-112764

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 852
-SubTopic 10
-Section 55
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=84165509&loc=d3e56145-112766

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- Definition

Amount recognized from the revaluation of assets and liabilities.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 852
-SubTopic 10
-Section 55
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=84165509&loc=d3e56145-112766

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-URI http://asc.fasb.org/extlink&oid=114872137&loc=d3e55730-112764

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Total amount of reorganization items.

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