Acquisitions and Divestitures - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended				9 Months Ended
	Jun. 30, 2013 Divestitures	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012 Divestitures	Jun. 30, 2013 Acquisition	Jun. 30, 2012 Acquisition
Acquisitions And Discontinued Operations [Line Items]
Number of acquisitions					2	3
Acquisition of businesses, net of cash acquired	$ 0		$ 0		$ 113	$ 30
Goodwill related to acquisition	220		52		220	52
Number of divestitures	1			2
Sales price of business divestiture	80
Number of acquisitions which increased Company's ownership from noncontrolling to controlling interest					1	2
Aggregate non-cash gain recorded due to acquisition	0		0		82	12
Sales price of divestiture	0		0	91	0	91
Gain (Loss) on sale of business	29		0	35	29	35
Reduction in goodwill related to business divestitures	15	5		29	15
Projected sales price of business divestiture	700
Purchase Price True-Up
Acquisitions And Discontinued Operations [Line Items]
Acquisition of businesses, net of cash acquired						(8)
Goodwill adjustment						72
Purchase Price
Acquisitions And Discontinued Operations [Line Items]
Acquisition of businesses, net of cash acquired					113	38
Power Solutions
Acquisitions And Discontinued Operations [Line Items]
Aggregate non-cash gain recorded due to acquisition						9
Automotive Experience
Acquisitions And Discontinued Operations [Line Items]
Aggregate non-cash gain recorded due to acquisition						$ 3