[Line Items] for Predecessor Debt [Table]

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- Definition

Date the original debt was issued, in CCYY-MM-DD format.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
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- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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Debt Obligations Predecessor Debt (Details) - USD ($) $ in Millions	3 Months Ended				12 Months Ended
	Mar. 31, 2017	Jun. 30, 2015	Mar. 31, 2013	Mar. 31, 2012	Dec. 31, 2018	Dec. 31, 2019	Nov. 01, 2019	Sep. 30, 2019	Feb. 01, 2017	Apr. 01, 2015	Jan. 01, 2013	Mar. 01, 2012
6.625% First Priority Senior Notes Due 2020 [Member]
Predecessor Debt [Line Items]
Debt Conversion, Original Debt, Issuance Date of Debt			Jan. 01, 2013	Mar. 01, 2012
Debt Instrument, Interest Rate, Stated Percentage					6.625%	0.00%		6.625%
Debt Instrument, Face Amount											$ 1,100	$ 450
Debt Instrument, Maturity Date					Apr. 15, 2020
13.75% Senior Secured Notes due 2022 [Member]
Predecessor Debt [Line Items]
Debt Conversion, Original Debt, Issuance Date of Debt	Feb. 01, 2017
Debt Instrument, Interest Rate, Stated Percentage					13.75%	0.00%		13.75%
Debt Instrument, Face Amount									$ 225
Debt Instrument, Maturity Date					Feb. 01, 2022
9.00% Second-Priority Senior Secured Notes Due 2020 [Member]
Predecessor Debt [Line Items]
Debt Conversion, Original Debt, Issuance Date of Debt					Nov. 01, 2010
Debt Instrument, Interest Rate, Stated Percentage					9.00%	0.00%		9.00%
Debt Instrument, Face Amount							$ 574
Debt Instrument, Maturity Date					Nov. 15, 2020
9.2% Debentures Due 2021 [Member]
Predecessor Debt [Line Items]
Debt Conversion, Original Debt, Issuance Date of Debt					Mar. 01, 1991
Debt Instrument, Interest Rate, Stated Percentage					9.20%	0.00%		9.20%
Debt Instrument, Face Amount					$ 74
Debt Instrument, Maturity Date					Mar. 15, 2021
7.875% Debentures Due 2023 [Member]
Predecessor Debt [Line Items]
Debt Conversion, Original Debt, Issuance Date of Debt					May 01, 1993
Debt Instrument, Interest Rate, Stated Percentage					7.875%	0.00%		7.875%
Debt Instrument, Face Amount					$ 189
Debt Instrument, Maturity Date					Feb. 15, 2023
10.00% First Priority Senior Notes Due 2020 [Member]
Predecessor Debt [Line Items]
Debt Conversion, Original Debt, Issuance Date of Debt		Apr. 01, 2015
Debt Instrument, Interest Rate, Stated Percentage					10.00%	0.00%		10.00%
Debt Instrument, Face Amount										$ 315
Debt Instrument, Maturity Date					Apr. 15, 2020
10.375% First-Priority Senion Secured Notes due 2022 [Member]
Predecessor Debt [Line Items]
Debt Conversion, Original Debt, Issuance Date of Debt	Feb. 01, 2017
Debt Instrument, Interest Rate, Stated Percentage					10.375%	0.00%
Debt Instrument, Face Amount									$ 560
Debt Instrument, Maturity Date					Feb. 01, 2022