Consolidated Statement Of Changes In Stockholders' Equity And Comprehensive Income (Parenthetical) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2010
Accumulated Other Comprehensive Income [Member]
Foreign currency translation adjustment, tax	$ 2	$ 3	$ 4
Change in unrealized loss on investments and derivative instruments, tax
Change in employee benefit plans	9		6
Non-controlling Interest [Member]
Net income attributable to noncontrolling interests, tax	7	4	3
Comprehensive Income [Member]
Foreign currency translation adjustment, tax	2	3	4
Change in unrealized loss on investments and derivative instruments, tax
Change in employee benefit plans	9		6
Net income attributable to noncontrolling interests, tax	$ 7	$ 4	$ 3