Consolidated Statement of Equity Statement - USD ($) $ in Millions	Total	Common stock	Additional paid-in-capital	Retained earnings	Accumulated other comprehensive income (loss)	Treasury stock	Noncontrolling interests in subsidiaries
Beginning balance at Sep. 30, 2018			$ 348	$ 23,072	$ (1,015)	$ (13,935)	$ 43
Statement [Roll Forward]
Stock plans			27
Net earnings common stockholders	$ 465			465
Dividends paid				(305)			(5)
Foreign currency translation	(35)				(35)
Pension and postretirement					13
Cash flow hedges	(15)				(15)
Purchases						(925)
Issued under stock plans						44
Net earnings							2
Other comprehensive income	(37)
Ending balance at Dec. 31, 2018	8,276	$ 477	375	23,252	(1,052)	(14,816)	40
Statement [Roll Forward]
Adoption of accounting standard update				20
Common stockholders' equity	8,236
Common stockholders' equity	8,233
Beginning balance at Sep. 30, 2019	8,273		393	24,199	(1,722)	(15,114)	40
Statement [Roll Forward]
Stock plans			54
Net earnings common stockholders	326			326
Dividends paid				(305)			(5)
Foreign currency translation	99				99
Pension and postretirement					28
Cash flow hedges	19				19
Purchases						(129)
Issued under stock plans						96
Net earnings							3
Other comprehensive income	146
Ending balance at Dec. 31, 2019	8,459	$ 477	$ 447	24,220	$ (1,576)	$ (15,147)	$ 38
Statement [Roll Forward]
Adoption of accounting standard update				$ 0
Common stockholders' equity	$ 8,421