Fair Value Measures (Fair Value of Financial Instruments) (Details) - USD ($) $ in Millions	Jun. 30, 2016	Sep. 30, 2015
Principal Amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	$ 6,061	$ 6,042
Estimate of Fair Value Measurement
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt Instrument, Fair Value Disclosure	3,721	4,420
Secured Debt \| Senior Secured Multi-Currency Revolver \| Principal Amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	17	18
Secured Debt \| Senior Secured Multi-Currency Revolver \| Estimate of Fair Value Measurement
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt Instrument, Fair Value Disclosure	16	17
Secured Debt \| Senior Secured Multi-Currency Asset-Based Revolver
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	60	55
Secured Debt \| Senior Secured Multi-Currency Asset-Based Revolver \| Principal Amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	60	55
Secured Debt \| Senior Secured Multi-Currency Asset-Based Revolver \| Estimate of Fair Value Measurement
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt Instrument, Fair Value Disclosure	43	42
Secured Debt \| Senior Secured Multi-Currency Foreign Asset-Based Revolver \| Principal Amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	53	20
Secured Debt \| Senior Secured Multi-Currency Foreign Asset-Based Revolver \| Estimate of Fair Value Measurement
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt Instrument, Fair Value Disclosure	37	15
Secured Debt \| Senior secured term B-3 loans \| Principal Amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	616	616
Secured Debt \| Senior secured term B-3 loans \| Estimate of Fair Value Measurement
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt Instrument, Fair Value Disclosure	475	532
Secured Debt \| Senior secured term B-4 loans \| Principal Amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	1	1
Secured Debt \| Senior secured term B-4 loans \| Estimate of Fair Value Measurement
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt Instrument, Fair Value Disclosure	1	1
Secured Debt \| Senior Secured Term B-6 Loans \| Principal Amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	537	537
Secured Debt \| Senior Secured Term B-6 Loans \| Estimate of Fair Value Measurement
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt Instrument, Fair Value Disclosure	398	461
Secured Debt \| Senior secured term B-4 loans \| Principal Amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	2,094	2,112
Secured Debt \| Senior secured term B-4 loans \| Estimate of Fair Value Measurement
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt Instrument, Fair Value Disclosure	1,486	1,666
Secured Debt \| Senior secured notes \| Principal Amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	1,009	1,009
Secured Debt \| Senior secured notes \| Estimate of Fair Value Measurement
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt Instrument, Fair Value Disclosure	726	800
Secured Debt \| 9% Senior secured notes \| Principal Amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	290	290
Secured Debt \| 9% Senior secured notes \| Estimate of Fair Value Measurement
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt Instrument, Fair Value Disclosure	214	242
Secured Debt \| 10.50% Senior secured notes \| Principal Amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	1,384	1,384
Secured Debt \| 10.50% Senior secured notes \| Estimate of Fair Value Measurement
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt Instrument, Fair Value Disclosure	$ 325	$ 644

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