Fair Value Of Financial Instruments (Carrying Amounts And Fair Values Of Company's Financial Instruments) (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2012	Sep. 30, 2011	Mar. 31, 2011	Sep. 30, 2010
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents, Carrying Amount	$ 366	$ 286	$ 366	$ 387
Cash and cash equivalents, Fair Value	366	286
GAM Promissory Notes and Inventory Note, Carrying Amount	263
GAM Promissory Notes and Inventory Note, Fair Value	273
Accounts and notes receivable, Carrying Amount	759	659
Accounts and notes receivable, Fair Value	759	659
Derivative instruments, Carrying Amount	2	1
Derivative instruments, Fair Value	2	1
Notes payable to banks, Carrying Amount	79	86
Notes payable to banks, Fair Value	79	86
Accounts payable and accrued liabilities, Carrying Amount	496	461
Accounts payable and accrued liabilities, Fair Value	496	461
Capital lease obligations, Carrying Amount	22	15
Capital lease obligations, Fair Value	22	15
Derivative instruments, Carrying Amount	34	39
Derivative instruments, Fair Value	34	39
Fixed Rate [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt, Carrying Amount	574	585
Long-term debt, Fair Value	630	633
Floating Rate [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt, Carrying Amount	10	15
Long-term debt, Fair Value	10	15
Fair Value, Inputs, Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
GAM Promissory Notes and Inventory Note, Carrying Amount	274
GAM Promissory Notes and Inventory Note, Fair Value	$ 274