Note 6. Debt and Financing Arrangements Long Term Debt (Details) - USD ($) $ in Millions	3 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Sep. 30, 2017
Debt Instrument [Line Items]
Capital Lease Obligations	$ 4		$ 4
Debt Issuance Costs, Net	37		38
Long-term Debt and Capital Lease Obligations, Including Current Maturities	3,463		3,442
Long-term Debt and Capital Lease Obligations, Current	2		2
Long-term Debt and Capital Lease Obligations	3,461		3,440
Interest Expense, Debt, Excluding Amortization	34	$ 33
Amortization of Debt Issuance Costs	2	2
Interest Income, Other	(1)	(1)
Gain (Loss) on Foreign Currency Fair Value Hedge Derivatives	(2)	1
Interest Income (Expense), Net	33	$ 35
Other Debt Obligations [Member]
Debt Instrument [Line Items]
Long-term Debt	2		1
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Long-term Debt	1,200		1,200
Euro Member Countries, Euro \| Unsecured Debt [Member]
Debt Instrument [Line Items]
Long-term Debt	1,197		1,180
United States of America, Dollars \| Unsecured Debt [Member]
Debt Instrument [Line Items]
Long-term Debt	900		900
European Union [Member] \| Euro Member Countries, Euro \| Unsecured Debt [Member]
Debt Instrument [Line Items]
Long-term Debt	$ 197		$ 195

Amount of amortization expense attributable to debt issuance costs.

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