Income Taxes Other Tax Matters (Details) - USD ($)	3 Months Ended							12 Months Ended
	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Sep. 30, 2015	Sep. 30, 2014	Jun. 30, 2014	Dec. 31, 2013	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2014
Other Tax Matters [Line Items]
Nondeductible expense related to restructuring and impairment								$ 126,000,000	$ 52,000,000	$ 75,000,000
Income tax provision								2,238,000,000	600,000,000	407,000,000
Effective Income Tax Rate Reconciliation, Other Adjustments, Amount		$ (85,000,000)			$ (51,000,000)			(31,000,000)	(24,000,000)	(24,000,000)
Restructuring and impairment costs								620,000,000	397,000,000	324,000,000
Effective Income Tax Rate Reconciliation, Repatriation of Foreign Earnings, Amount			$ 780,000,000
Post sale contingent tax indemnification liabilities	$ 290,000,000							290,000,000
Business Divestitures, Not Specific
Other Tax Matters [Line Items]
Post sale contingent tax indemnification liabilities	255,000,000							255,000,000
(Loss) on divestiture	(12,000,000)
Global Workplace Solutions
Other Tax Matters [Line Items]
Effective Income Tax Rate Reconciliation, Repatriation of Foreign Earnings, Amount									680,000,000	35,000,000
Discontinued Operation, Income from Discontinued Operation, before Income Tax									$ 1,203,000,000	$ 119,000,000
Headliner and Sunvisor [Member]
Other Tax Matters [Line Items]
(Loss) on divestiture						$ 95,000,000
Income tax expense from disposal						$ 38,000,000
Automotive Experience Interiors | Business Divestitures, Not Specific
Other Tax Matters [Line Items]
(Loss) on divestiture							$ (9,000,000)
Automotive Experience Interiors | Yanfeng Automotive Trim Systems [Member]
Other Tax Matters [Line Items]
Discontinued Operation, Income from Discontinued Operation, before Income Tax				$ (145,000,000)
Discontinued Operation, Gain on Disposal of Discontinued Operation, Net of Tax				38,000,000
Automotive Experience Interiors | Interiors
Other Tax Matters [Line Items]
Effective Income Tax Rate Reconciliation, Repatriation of Foreign Earnings, Amount	75,000,000			$ 223,000,000
2016 Restructuring Plan [Member]
Other Tax Matters [Line Items]
Restructuring and impairment costs								620,000,000
Tyco Merger [Member]
Other Tax Matters [Line Items]
Income tax provision	$ 137,000,000
Adient spin-off [Member]
Other Tax Matters [Line Items]
Income tax provision								121,000,000
Substantial business reorganizations [Member]
Other Tax Matters [Line Items]
Effective Income Tax Rate Reconciliation, Other Adjustments, Amount								$ 1,891,000,000