Consolidated Statements of Financial Position (Parenthetical) - USD ($) $ in Millions	Sep. 30, 2016	Sep. 30, 2015
Statement of Financial Position [Abstract]
Allowance for doubtful accounts	$ 116	$ 82
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	1,800,000,000	1,800,000,000
Common stock, shares issued	0	717,039,108
Treasury stock, at cost, shares	0	69,671,840