Derivative Financial Instruments (Effect of Derivative Instruments) (Details) - USD ($) $ in Millions |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Mar. 31, 2017 |
Mar. 31, 2016 |
Mar. 31, 2017 |
Mar. 31, 2016 |
|
| Cost of Sales [Member] | ||||
| Derivative Financial Instruments | ||||
| Gain (Loss) on Foreign Currency Derivative Instruments Not Designated as Hedging Instruments | $ 0 | $ (2) | $ (1) | $ (5) |
| Fair Value Hedging [Member] | Interest Expense [Member] | ||||
| Derivative Financial Instruments | ||||
| Gain (loss) recognized from interest rate swaps | 2 | 2 | 4 | 5 |
| Cash Flow Hedging [Member] | AOCL [Member] | ||||
| Derivative Financial Instruments | ||||
| Amount of gain (loss) recognized in AOCL (effective portion, before deferred tax impact) | 4 | 0 | 0 | (1) |
| Cash Flow Hedging [Member] | Cost of Sales [Member] | ||||
| Derivative Financial Instruments | ||||
| Amount of loss reclassified from AOCL into income | $ (2) | $ (3) | $ (3) | $ (5) |