Restructuring, Separation, Transition and Other Costs (Schedule of the Restructuring and Separation Liabilities Summary) (Details) - USD ($) $ in Millions	6 Months Ended
	Sep. 30, 2016
Restructuring Reserve [Roll Forward]
Balance as of April 1, 2016	$ 33
Costs, Net of Adjustments	99
Cash Payments	(84)
Non-Cash Charges	(14)
Balance as of September 30, 2016	34
Fiscal 2015 Plan
Restructuring Reserve [Roll Forward]
Balance as of April 1, 2016	29
Costs, Net of Adjustments	12
Cash Payments	(32)
Non-Cash Charges	0
Balance as of September 30, 2016	9
Cumulative Incurred to Date	468
Fiscal 2017 Plan
Restructuring Reserve [Roll Forward]
Balance as of April 1, 2016	4
Costs, Net of Adjustments	87
Cash Payments	(52)
Non-Cash Charges	(14)
Balance as of September 30, 2016	25
Cumulative Incurred to Date	91
Fiscal 2017 Plan | Severance costs
Restructuring Reserve [Roll Forward]
Balance as of April 1, 2016	0
Costs, Net of Adjustments	38
Cash Payments	(31)
Non-Cash Charges	0
Balance as of September 30, 2016	7
Cumulative Incurred to Date	38
Fiscal 2017 Plan | Other exit and disposal costs
Restructuring Reserve [Roll Forward]
Balance as of April 1, 2016	4
Costs, Net of Adjustments	35
Cash Payments	(21)
Non-Cash Charges	0
Balance as of September 30, 2016	18
Cumulative Incurred to Date	39
Fiscal 2017 Plan | Asset write-offs
Restructuring Reserve [Roll Forward]
Balance as of April 1, 2016	0
Costs, Net of Adjustments	14
Cash Payments	0
Non-Cash Charges	(14)
Balance as of September 30, 2016	0
Cumulative Incurred to Date	$ 14