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Short-term Borrowings and Other Debt Obligations Schedule of Short-term Debt (Details) - USD ($) $ in Millions	Dec. 31, 2019	Sep. 30, 2019	Dec. 31, 2018	Jun. 30, 2017	Jun. 26, 2017
Short-term Debt [Line Items]
Current Portion of Long-term Debt	$ 10		$ 57
Short-term Borrowings and Current Portion of Long-term Debt	13		383
364 Day Secured RCF [Member]
Short-term Debt [Line Items]
Short-term Debt	$ 0		317
Other short-term bank loans [Member]
Short-term Debt [Line Items]
Short-term Debt		$ 3	9
Long-term Debt, Current Maturities		10	57
A&R Credit Agreement [Member]
Short-term Debt [Line Items]
Short-term Debt		$ 0	$ 0
Senior Notes, 9.875 Percent due 2024
Short-term Debt [Line Items]
Long-term Debt				$ 540	$ 250
Senior Notes [Member] \| Senior Notes, 9.875 Percent due 2024
Short-term Debt [Line Items]
Debt Instrument, Interest Rate, Stated Percentage					9.875%