Reconciliation of the numerators and denominators (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended		12 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2014
Earnings Per Share [Abstract]
Cash dividends common, per share	$ 0.29	$ 0.26	$ 1.16	$ 1.04	$ 0.88
Income (loss) from continuing operations			$ (868)	$ 1,439	$ 1,404
Income Available to Common Shareholders
Income (loss) from discontinued operations			0	(124)	189
Net Income (Loss) Attributable to Parent			$ (868)	$ 1,563	$ 1,215
Weighted Average Shares Outstanding
Basic weighted average shares outstanding			667.4	655.2	666.9
Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements			0.0	6.3	7.9
Effect of dilutive securities:
Potentially dilutive stock options and unvested restricted stock			5.2
Diluted weighted average shares outstanding			667.4	661.5	674.8
Antidilutive Securities
Options to purchase common shares			0.0	0.4	0.1