Acquisitions, Goodwill and Intangible Assets - Pro Forma Results of Operations (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Reported Results
Sales	$ 2,011	$ 1,193
Net income	$ 280	$ 145
Basic earnings per share (in dollars per share)	$ 1.71	$ 1.11
Diluted earnings per share (in dollars per share)	$ 1.69	$ 1.10
B/E Aerospace
Pro Forma Results
Sales		$ 1,923
Net income attributable to common shareowners		$ 197
Basic earnings per share (in dollars per share)		$ 1.22
Diluted earnings per share (in dollars per share)		$ 1.21