Financing Arrangement (Line of Credit Facility) (Details) - Revolving Credit Facility [Member] $ in Millions |
6 Months Ended |
|---|---|
|
Sep. 30, 2016
USD ($)
| |
| Line of Credit Facility [Line Items] | |
| Credit Facility, Maximum Borrowing Capacity | $ 500 |
| Option To Request Additional Commitments On Credit Facility | 250 |
| Debt issuance costs | $ 2 |
| Credit Facility, Initiation Date | Mar. 19, 2015 |
| Credit Facility, Expiration Date | Mar. 19, 2020 |
| Line of Credit Facility Term | 5 years |