Fair Value Measurements 3 (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2012
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Facility exit reserve	$ 49	$ 84	$ 39	$ 53
Facility Exit
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Facility exit reserve	21	29	23	40
Facility Exit | Accrued Expenses and Other Current Liabilities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Facility exit reserve	4	11
Facility Exit | Other Noncurrent Liabilities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Facility exit reserve	$ 17	$ 18