Segment Information 2 (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Revenue from the United States and international locations
Total revenue	$ 1,140	$ 1,152	$ 2,268	$ 2,297
United States [Member]
Revenue from the United States and international locations
Total revenue	687	685	1,360	1,368
Europe [Member]
Revenue from the United States and international locations
Total revenue	267	266	531	538
Other [Member]
Revenue from the United States and international locations
Total revenue	$ 186	$ 201	$ 377	$ 391