Other Assets (Narrative) (Details) $ in Millions |
3 Months Ended | 6 Months Ended | 12 Months Ended | ||
|---|---|---|---|---|---|
|
Mar. 31, 2016
USD ($)
Joint_Venture
|
Mar. 31, 2015
USD ($)
|
Mar. 31, 2016
USD ($)
Joint_Venture
|
Mar. 31, 2015
USD ($)
|
Sep. 30, 2015
USD ($)
|
|
| Schedule of Investments [Line Items] | |||||
| Number of equity affiliates (joint ventures) | Joint_Venture | 8 | 8 | |||
| Ownership Percentage | 50.00% | 50.00% | |||
| Sales to equity affiliates | $ 55 | $ 49 | $ 101 | $ 88 | |
| Deferred profit generated from sales to equity affiliates | $ 1 | $ 1 | |||
| Exchange and rental assets estimated useful life | 15 years | ||||
| Depreciation expense, exchange and rental assets | 3 | $ 3 | $ 5 | $ 5 | |
| ACCEL Flight Simulation Co., Ltd [Member] | |||||
| Schedule of Investments [Line Items] | |||||
| Payments to Acquire Interest in Subsidiaries and Affiliates | $ 5 | ||||
| Future Payments to Acquire Equity Method Investment | $ 2 | $ 2 | |||