Chapter 11 Bankruptcy Chapter 11 Bankruptcy (Details) - USD ($)	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	300,000,000	$ 100,000,000
Due Within One Year	$ 88,000,000	438,000,000	$ 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
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	58,410,731	170,605,906	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	$ 0
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

[Line Items] for Chapter 11 Bankruptcy [Table]

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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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