Fresh-Start Accounting - Post-Petition Liabilities and Allowed Claims (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017	Feb. 28, 2017
Reorganizations [Abstract]
Liabilities subject to compromise	$ 100	$ 35,000	$ 1,000,336
Pre-petition debt not classified as subject to compromise			891,259
Post-petition liabilities			245,702
Total post-petition liabilities and allowed claims			2,137,297
Reorganization value of assets immediately prior to implementation of the Plan			(1,722,585)
Excess post-petition liabilities and allowed claims			$ 414,712

Amount attributed to the reconstituted entity, as well as the expected net realizable value of those assets that will be disposed before reconstitution occurs.

Reference 1: 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

Reference 2: 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 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 852
-SubTopic 10
-Section 55
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=84165509&loc=d3e56426-112766

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