Restructuring And Other Charges (Narrative) (Details) (USD $) In Millions, unless otherwise specified					11 Months Ended	41 Months Ended	11 Months Ended		11 Months Ended			41 Months Ended	30 Months Ended	39 Months Ended		30 Months Ended				9 Months Ended	30 Months Ended	9 Months Ended	30 Months Ended	39 Months Ended	42 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2011	Mar. 31, 2010	Mar. 31, 2013 Fiscal 2013 Restructuring [Member]	Aug. 31, 2016 Fiscal 2013 Restructuring [Member] Settled by August 2016 [Member]	Mar. 31, 2013 Fiscal 2013 Restructuring [Member] Workforce [Member]	Mar. 31, 2012 Fiscal 2013 Restructuring [Member] Workforce [Member]	Mar. 31, 2013 Fiscal 2013 Restructuring [Member] License Termination Cost [Member]	Mar. 31, 2013 Fiscal 2013 Restructuring [Member] Facilities-Related [Member]	Mar. 31, 2012 Fiscal 2013 Restructuring [Member] Facilities-Related [Member]	Aug. 31, 2016 Fiscal 2013 Restructuring [Member] License and Lease Termination Costs [Member] Settled by August 2016 [Member]	Mar. 31, 2013 Fiscal 2011 Restructuring [Member]	Jun. 30, 2016 Fiscal 2011 Restructuring [Member] Settled by June 2016 [Member]	Mar. 31, 2013 Fiscal 2011 Restructuring [Member] Settled by June 2016 [Member]	Mar. 31, 2013 Fiscal 2011 Restructuring [Member] Workforce [Member]	Mar. 31, 2012 Fiscal 2011 Restructuring [Member] Workforce [Member]	Mar. 31, 2011 Fiscal 2011 Restructuring [Member] Workforce [Member]	Mar. 31, 2010 Fiscal 2011 Restructuring [Member] Workforce [Member]	Dec. 31, 2012 Fiscal 2011 Restructuring [Member] Workforce [Member] Settled by June 2016 [Member]	Mar. 31, 2013 Fiscal 2011 Restructuring [Member] Amended Licensing Agreements And Other Asset Impairment [Member]	Dec. 31, 2012 Fiscal 2011 Restructuring [Member] Amended Licensing Agreements And Other Asset Impairment [Member] Settled by June 2016 [Member]	Mar. 31, 2013 Fiscal 2011 Restructuring [Member] Developer Commitments [Member]	Jun. 30, 2016 Fiscal 2011 Restructuring [Member] Accretion Of Interest Related to Our Amended Licensing and Developer Agreements [Member] Settled by June 2016 [Member]	Sep. 30, 2016 Other Restructurings and Reorganization [Member] Settled By September2016 [Member]	Mar. 31, 2013 Other Restructurings and Reorganization [Member] Settled By September2016 [Member]
Restructuring And Other Charges [Line Items]
Announcement date of restructuring plan					May 07, 2012
Restructuring charges incurred					$ 22		$ 10		$ 9	$ 3			$ 174			$ 12					$ 131		$ 31
Expected restructuring charges												3								12		170		8
Settlement date of restructuring charges					Mar. 31, 2013	Aug. 31, 2016							Mar. 31, 2011	Jun. 30, 2016											Sep. 30, 2016
Expected restructuring charges, minimum														180
Expected restructuring charges, maximum														185
Restructuring reserve and accrual	$ 62	$ 78	$ 117	$ 29			$ 0	$ 0		$ 2	$ 0				$ 57		$ 0	$ 3	$ 0							$ 2