Debt and Financing Activities - Accounts Receivable Facilities (Details) - Accounts Receivable Factoring Facility - USD ($)	6 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Mar. 31, 2016
Debt Instrument [Line Items]
Proceeds from borrowings under Accounts Receivable Facilities	$ 6,000,000	$ 883,000,000
Repayments made towards Accounts Receivable Facilities	13,000,000	$ 887,000,000
Secured borrowings outstanding	$ 0		$ 7,000,000