Debt Obligations Level 4 (Details) - Scheduled Maturities - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Debt and Commitments Maturities [Line Items]
Long-term Debt, Maturities, Repayments of Principal in Next Twelve Months	$ 3,706
Operating Leases, Future Minimum Payments Due, Next Twelve Months	33
Capital Leases, Future Minimum Payments Due, Next Twelve Months	15
Long-term Debt, Maturities, Repayments of Principal in Year Two	34
Capital Leases, Future Minimum Payments Due in Two Years	20
Operating Leases, Future Minimum Payments, Due in Two Years	24
Long-term Debt, Maturities, Repayments of Principal in Year Three	2
Capital Leases, Future Minimum Payments Due in Three Years	13
Operating Leases, Future Minimum Payments, Due in Three Years	20
Long-term Debt, Maturities, Repayments of Principal in Year Four	1
Capital Leases, Future Minimum Payments Due in Four Years	26
Operating Leases, Future Minimum Payments, Due in Four Years	13
Long-term Debt, Maturities, Repayments of Principal in Year Five	0
Capital Leases, Future Minimum Payments Due in Five Years	9
Operating Leases, Future Minimum Payments, Due in Five Years	10
Long-term Debt, Maturities, Repayments of Principal after Year Five	6
Capital Leases, Future Minimum Payments Due Thereafter	1
Operating Leases, Future Minimum Payments, Due Thereafter	61
Capital Leases, Future Minimum Payments Due	84
Operating Leases, Future Minimum Payments Due	161
Amount representing interest	(18)
Present value of minimum payments	66
Non-affiliated Debt [Member]
Debt and Commitments Maturities [Line Items]
Total minimum payments	$ 3,749
6.625% First Priority Senior Notes Due 2020 [Member]
Debt and Commitments Maturities [Line Items]
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 and Commitments Maturities [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	10.00%	10.00%
Debt Instrument, Maturity Date	Apr. 15, 2020
10.375% First-Priority Senion Secured Notes due 2022 [Member]
Debt and Commitments Maturities [Line Items]
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 and Commitments Maturities [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	13.75%	13.75%
Debt Instrument, Maturity Date	Feb. 01, 2022
9.00% Second-Priority Senior Secured Notes Due 2020 [Member]
Debt and Commitments Maturities [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	9.00%	9.00%
Debt Instrument, Maturity Date	Nov. 15, 2020
9.2% Debentures Due 2021 [Member]
Debt and Commitments Maturities [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	9.20%	9.20%
Debt Instrument, Maturity Date	Mar. 15, 2021
7.875% Debentures Due 2023 [Member]
Debt and Commitments Maturities [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	7.875%	7.875%
Debt Instrument, Maturity Date	Feb. 15, 2023
Australia Facility Due 2021 [Member]
Debt and Commitments Maturities [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	4.80%
Australia Facility Due 2017 [Member]
Debt and Commitments Maturities [Line Items]
Debt Instrument, Interest Rate, Stated Percentage		4.60%
Brazilian Bank Loans [Member]
Debt and Commitments Maturities [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	10.00%	9.90%
Other [Member]
Debt and Commitments Maturities [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	5.30%	5.00%

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Amount of minimum lease payments for capital leases.

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Amount of minimum lease payments for capital leases due in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Present value of minimum lease payments for capital leases net of executory costs, including amounts paid by the lessee to the lessor for insurance, maintenance and taxes.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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