Restructuring And Other Charges (Narrative) (Details) (USD $) In Millions, unless otherwise specified											70 Months Ended
	Sep. 30, 2014	Mar. 31, 2014	Mar. 31, 2013	Sep. 30, 2014 Fiscal 2011 Restructuring	Sep. 30, 2014 Fiscal 2011 Restructuring Workforce	Sep. 30, 2014 Fiscal 2011 Restructuring Amended Licensing Agreements And Other Asset Impairment	Sep. 30, 2014 Fiscal 2011 Restructuring Developer Commitments	Sep. 30, 2014 Fiscal 2011 Restructuring Other Restructuring Costs [Member]	Mar. 31, 2014 Fiscal 2011 Restructuring Other Restructuring Costs [Member]	Mar. 31, 2013 Fiscal 2011 Restructuring Other Restructuring Costs [Member]	Apr. 30, 2020 Other Restructurings and Reorganization	Sep. 30, 2014 Other Restructurings and Reorganization Expected By April 2020	Sep. 30, 2014 Other Restructurings and Reorganization Other Restructuring Costs [Member]	Mar. 31, 2014 Other Restructurings and Reorganization Other Restructuring Costs [Member]	Mar. 31, 2013 Other Restructurings and Reorganization Other Restructuring Costs [Member]
Restructuring And Other Charges
Restructuring and Related Cost, Cost Incurred to Date				$ 172	$ 12	$ 129	$ 31
Restructuring Reserve	$ 35	$ 50	$ 62					$ 32	$ 47	$ 57		$ 3	$ 1	$ 1	$ 1
Restructuring and related activities expected completion date											Apr. 30, 2020