Fresh Start Accounting - Schedule of Reorganization Items, net (Detail) - USD ($) $ in Thousands	4 Months Ended	8 Months Ended	12 Months Ended
May 04, 2017	Dec. 31, 2017	Dec. 31, 2019	Dec. 31, 2018
Fresh Start Adjustment [Line Items]
Gain on settlement of liabilities subject to compromise		$ 0	$ 0	$ 0
Fresh start valuation adjustments		0	0	0
Professional fees		(724)	(430)	(864)
Other		(395)	(627)	(1,283)
Reorganization items, net		$ (1,119)	$ (1,057)	$ (2,147)
Predecessor [Member]
Fresh Start Adjustment [Line Items]
Gain on settlement of liabilities subject to compromise	$ 758,764
Fresh start valuation adjustments	(827,120)
Professional fees	(19,824)
Other	(594)
Reorganization items, net	$ (88,774)

Amount of reorganization items related to discharge of claims and liabilities upon emergence from bankruptcy.

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

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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Amount of reorganization items related to legal and advisory professional fees related to entities in bankruptcy.

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Amount recognized from the revaluation of assets and liabilities.

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