Acquisitions and Divestitures Pro Forma Financial Information (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended	9 Months Ended
Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Business Acquisition [Line Items]
Net sales	$ 4,132	$ 4,101	$ 11,677	$ 11,864
Net earnings from continuing operations common stockholders	$ 426	$ 436	$ 1,155	$ 972
Diluted earnings per share from continuing operations	$ 0.66	$ 0.67	$ 1.78	$ 1.50
Net income (loss)	$ 425	$ 489	$ 1,040	$ 1,219
Fair Value Adjustment To Inventory & Backlog [Member]
Business Acquisition [Line Items]
Net income (loss)		$ 11		120
Acquisition-related Costs [Member]
Business Acquisition [Line Items]
Net income (loss)				$ 50

Per diluted share amount of pro forma income from continuing operations, after tax, as if the business combination had been completed at the beginning of a period.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
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