Equity Roll Forward (Schedule Of Change In Equity) (Details) - USD ($) $ in Millions	3 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Sep. 30, 2018
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	$ 8,990
Net earnings common stockholders	465	$ 392
Foreign currency translation	(35)	7
Cash flow hedges	(15)	(3)
Common stockholders' equity	8,236	8,349	$ 8,947
Ending balance	8,276	8,388
Common stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Ending balance	477	477
Additional paid-in-capital
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	348	297
Stock plans	27	9
Ending balance	375	306
Retained earnings
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	23,072	21,995
Net earnings common stockholders	465	392
Dividends paid	(305)	(311)
Adoption of accounting standard updates	20	3
Ending balance	23,252	22,079
Accumulated other comprehensive income (loss)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	(1,015)	(1,019)
Foreign currency translation	(35)	7
Pension and postretirement	13	23
Cash flow hedges	(15)	(3)
Ending balance	(1,052)	(992)
Treasury stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	(13,935)	(13,032)
Purchases	(925)	(500)
Issued under stock plans	44	11
Ending balance	(14,816)	(13,521)
Noncontrolling interests in subsidiaries
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	43	52
Dividends paid	(5)	(15)
Net earnings	2	2
Ending balance	$ 40	$ 39

Value of treasury stock reissued during the period under stock plans and other.

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Amount after tax of increase (decrease) to equity or (increase) decrease to net assets, resulting from the cumulative effect adjustment of a new accounting principle applied in the period of adoption.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Amount of Net Income (Loss) attributable to redeemable noncontrolling interest.

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