Debt Obligations (Details) - USD ($) $ in Millions	6 Months Ended
Jun. 30, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Due Within One Year	$ 82	$ 125
Debt Issuance Costs, Gross	(35)	(41)
Long-term debt	3,678	3,584
ABL Facility [Domain]
Debt Instrument [Line Items]
Due Within One Year	0	0
Long-term debt	120	81
6.625% First Priority Senior Notes Due 2020 [Member]
Debt Instrument [Line Items]
Debt Instrument, Unamortized Premium	2	2
Due Within One Year	0	0
Long-term debt	$ 1,552	$ 1,552
Debt Instrument, Interest Rate, Stated Percentage	6.625%	6.625%
Debt Instrument, Maturity Date	Apr. 15, 2020
10.00% First Priority Senior Notes Due 2020 [Member]
Debt Instrument [Line Items]
Due Within One Year	$ 0	$ 0
Long-term debt	$ 315	$ 315
Debt Instrument, Interest Rate, Stated Percentage	10.00%	10.00%
10.375% First-Priority Senion Secured Notes due 2022 [Member]
Debt Instrument [Line Items]
Due Within One Year	$ 0	$ 0
Long-term debt	$ 560	$ 560
Debt Instrument, Interest Rate, Stated Percentage	10.375%	10.375%
Debt Instrument, Maturity Date	Feb. 01, 2022
13.75% Senior Secured Notes due 2022 [Member]
Debt Instrument [Line Items]
Due Within One Year	$ 0	$ 0
Long-term debt	$ 225	$ 225
Debt Instrument, Interest Rate, Stated Percentage	13.75%	13.75%
9.00% Second-Priority Senior Secured Notes Due 2020 [Member]
Debt Instrument [Line Items]
Due Within One Year	$ 0	$ 0
Long-term debt	$ 574	$ 574
Debt Instrument, Interest Rate, Stated Percentage	9.00%	9.00%
Debt Instrument, Maturity Date	Nov. 15, 2020
9.2% Debentures Due 2021 [Member]
Debt Instrument [Line Items]
Due Within One Year	$ 0	$ 0
Long-term debt	$ 74	$ 74
Debt Instrument, Interest Rate, Stated Percentage	9.20%	9.20%
Debt Instrument, Maturity Date	Mar. 15, 2021
7.875% Debentures Due 2023 [Member]
Debt Instrument [Line Items]
Due Within One Year	$ 0	$ 0
Long-term debt	$ 189	$ 189
Debt Instrument, Interest Rate, Stated Percentage	7.875%	7.875%
Debt Instrument, Maturity Date	Feb. 15, 2023
Australia Facility Due 2021 [Member]
Debt Instrument [Line Items]
Due Within One Year	$ 4	$ 50
Long-term debt	$ 33	0
Debt Instrument, Maturity Date	Dec. 05, 2021
Brazilian Bank Loans [Member]
Debt Instrument [Line Items]
Due Within One Year	$ 37	34
Long-term debt	10	9
Capital Leases [Member]
Debt Instrument [Line Items]
Due Within One Year	8	5
Long-term debt	57	44
Other [Member]
Debt Instrument [Line Items]
Due Within One Year	33	36
Long-term debt	4	2
Unamortized debt issuance costs [Member]
Debt Instrument [Line Items]
Due Within One Year	$ 0	$ 0

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

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