Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Goodwill and Other Intangible Assets Goodwill Additional Information (Details) - USD ($)	3 Months Ended	12 Months Ended
	Sep. 30, 2014	Sep. 30, 2016	Sep. 30, 2015
Goodwill [Line Items]
Goodwill, written off related to divestiture		$ 19,000,000	$ 29,000,000
Goodwill impairment loss		0	0
Goodwill	$ 7,127,000,000	7,101,000,000	6,824,000,000
Building Efficiency
Goodwill [Line Items]
Goodwill, written off related to divestiture		3,000,000
Goodwill		1,697,000,000
Building Efficiency \| Building Efficiency Other
Goodwill [Line Items]
Goodwill, written off related to divestiture		13,000,000	0
Goodwill impairment loss	47,000,000
Goodwill	345,000,000	301,000,000	310,000,000
Automotive Experience \| Automotive Experience Interiors [Member]
Goodwill [Line Items]
Goodwill impairment loss	430,000,000
Automotive Experience \| Interiors
Goodwill [Line Items]
Goodwill, written off related to divestiture			9,000,000
Goodwill	$ 0		0
Latin America [Member] \| Building Efficiency Other
Goodwill [Line Items]
Goodwill		$ 0	$ 0