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Debtor reorganization item, equity backstop

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Debtor reorganization items, debt backstop

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Rights offering

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Settlement note

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Face amount or stated value per share of common stock.

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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

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Number of shares issued which are neither cancelled nor held in the treasury.

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Value of outstanding derivative securities that permit the holder the right to purchase securities (usually equity) from the issuer at a specified price.

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Chapter 11 Bankruptcy Chapter 11 Bankruptcy (Details) - USD ($)	Sep. 30, 2019	Jul. 01, 2019	Jun. 30, 2019	Dec. 31, 2018
Chapter 11 Bankruptcy [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity		$ 350,000,000
Long-term debt		1,658,000,000
Rights offering	$ 100,000,000	$ 300,000,000
Due Within One Year	87,000,000			$ 3,716,000,000
Debtor reorganization item, equity backstop	24,000,000
Debtor reorganization items, debt backstop	80,000,000
Settlement note	$ 2,500,000
Shares, Outstanding		100		82,556,847
Common Stock, Par or Stated Value Per Share	$ 0.01	$ 0.01		$ 0.01
Warrants and Rights Outstanding		$ 10,307,778
Common Stock, Shares, Issued	100	58,410,731		170,605,906
10.00% First Priority Senior Notes Due 2020 [Member]
Chapter 11 Bankruptcy [Line Items]
Due Within One Year	$ 0			$ 315,000,000
Debt Instrument, Interest Rate, Stated Percentage	10.00%			10.00%
DIP Term Loan Facility [Member]
Chapter 11 Bankruptcy [Line Items]
Due Within One Year			$ 350,000,000
6.625% First Priority Senior Notes Due 2020 [Member]
Chapter 11 Bankruptcy [Line Items]
Due Within One Year	$ 0			$ 1,550,000,000
Debt Instrument, Interest Rate, Stated Percentage	6.625%			6.625%
13.75% Senior Secured Notes due 2022 [Member]
Chapter 11 Bankruptcy [Line Items]
Due Within One Year	$ 0			$ 225,000,000
Debt Instrument, Interest Rate, Stated Percentage	13.75%			13.75%
9.00% Second-Priority Senior Secured Notes Due 2020 [Member]
Chapter 11 Bankruptcy [Line Items]
Due Within One Year	$ 0			$ 574,000,000
Debt Instrument, Interest Rate, Stated Percentage	9.00%			9.00%
9.2% Debentures Due 2021 [Member]
Chapter 11 Bankruptcy [Line Items]
Due Within One Year	$ 0			$ 74,000,000
Debt Instrument, Interest Rate, Stated Percentage	9.20%			9.20%
7.875% Debentures Due 2023 [Member]
Chapter 11 Bankruptcy [Line Items]
Due Within One Year	$ 0			$ 189,000,000
Debt Instrument, Interest Rate, Stated Percentage	7.875%			7.875%
Minimum [Member]
Chapter 11 Bankruptcy [Line Items]
Reorganization Value	$ 2,900,000,000
Maximum [Member]
Chapter 11 Bankruptcy [Line Items]
Reorganization Value	$ 3,300,000,000