Bankruptcy proceedings.

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- Definition

Plan of reorganization, amount of equity securities to be issued.

+ References

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- Definition

Amount of bankruptcy claim settled.

+ References

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- Definition

United States Bankruptcy Court where petition for bankruptcy was filed.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 852
-SubTopic 10
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Date petition for bankruptcy filed with the bankruptcy court, in CCYY-MM-DD format.

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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-Topic 210
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- Definition

Amount debtor-in-possession financing arranged (but not necessarily all borrowed).

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- Definition

Date the plan of reorganization is approved by the bankruptcy court, in CCYY-MM-DD format.

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Date the plan of reorganization is effective, in CCYY-MM-DD format.

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Chapter 11 Proceedings - Additional Information (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2018	Oct. 06, 2017	Apr. 12, 2017	Feb. 08, 2017
Bankruptcy Proceedings [Line Items]
Petition date	Apr. 29, 2016
Court where petition was filed	United States Bankruptcy Court for the Southern District of Texas (the “Bankruptcy Court”)
Plan confirmed date	Mar. 14, 2017
Plan expected to be effective date	Apr. 12, 2017
Claims settled		$ 399.0
Senior Unsecured Notes Due 2018
Bankruptcy Proceedings [Line Items]
Claims settled			$ 450.0
5.75% Senior Notes Due 2018
Bankruptcy Proceedings [Line Items]
Stated interest rate			5.75%
Senior Unsecured Notes Due 2024
Bankruptcy Proceedings [Line Items]
Claims settled			$ 850.0
6.125% Senior Notes Due 2024
Bankruptcy Proceedings [Line Items]
Stated interest rate			6.125%
Prepetition Credit Agreement
Bankruptcy Proceedings [Line Items]
Claims settled			$ 999.0
Prepetition Senior Notes
Bankruptcy Proceedings [Line Items]
Claims settled			1,460.0
Barclays Bank PLC
Bankruptcy Proceedings [Line Items]
Secured and unsecured financing provided by Barclays				$ 2,400.0
BCA
Bankruptcy Proceedings [Line Items]
Rights offering, aggregate purchase price			$ 580.0