Reclassification of emergence credit facility to long term debt.

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- Definition

Reorganized predecessor percentage of voting shares to voting share holders.

+ References

No definition available.

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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

The increase (decrease) during the reporting period in the carrying amount of asset retirement obligations.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3602-108585

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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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- Definition

Amount of cash outflow for payment of an obligation from a lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3291-108585

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(f))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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Fresh Start Accounting - Additional Information (Detail) - USD ($)		4 Months Ended	8 Months Ended	12 Months Ended
	May 04, 2017	May 04, 2017	Dec. 31, 2017	Dec. 31, 2019	Dec. 31, 2018
Fresh Start Adjustment [Line Items]
Enterprise value	$ 800,000,000	$ 800,000,000
Repayment of predecessor's revolving credit facility			$ 63,000,000	$ 134,000,000	$ 397,000,000
Fresh Start Adjustments [Member]
Fresh Start Adjustment [Line Items]
Decrease in asset retirement obligations	62,900,000
Predecessor [Member]
Fresh Start Adjustment [Line Items]
Repayment of predecessor's revolving credit facility		98,252,000
Predecessor [Member] \| Reorganization Adjustments [Member]
Fresh Start Adjustment [Line Items]
Repayment of predecessor's revolving credit facility	24,800,000
Reclassification of borrowings under the emergence credit facility to long-term debt	430,000,000
Maximum [Member]
Fresh Start Adjustment [Line Items]
Percentage of voting shares to be received by voting share holders				50.00%
Enterprise value	$ 900,000,000	$ 900,000,000
Maximum [Member] \| Predecessor [Member]
Fresh Start Adjustment [Line Items]
Percentage of voting shares to be received by voting share holders	50.00%	50.00%
Minimum [Member]
Fresh Start Adjustment [Line Items]
Enterprise value	$ 700,000,000	$ 700,000,000