Discontinued Operations (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended		12 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Mar. 31, 2017	Mar. 31, 2016	Sep. 30, 2017	Sep. 30, 2016
Disposal Group, Including Discontinued Operation, Income Statement Disclosures [Abstract]
Earnings (Loss), net of tax	$ (84)	$ 2	$ (139)	$ 48
Disposal Group, Including Discontinued Operation, Additional Disclosures [Abstract]
Cash from operating activities				190
Cash from investing activities			5,051	(38)
Gain on sale of business, net of tax			14
Combined, Network Power and Power Generation, motors and Drives Business [Member] | Discontinued Operations, Held-for-sale or Disposed of by Sale [Member]
Disposal Group, Including Discontinued Operation, Income Statement Disclosures [Abstract]
Net sales	97	1,356	1,037	2,742
Cost of sales	75	902	701	1,813
SG&A	21	341	263	686
Other (income) deductions, net	4	55	(417)	115
Earnings (Loss) before income taxes	(3)	58	490	128
Income taxes	81	56	629	80
Earnings (Loss), net of tax	(84)	2	(139)	48
Disposal Group, Including Discontinued Operation, Balance Sheet Disclosures [Abstract]
Accounts receivables						$ 1,492
Inventories						578
Other current assets						130
Property, plant & equipment, net						611
Goodwill						2,691
Other noncurrent assets						528
Total assets held-for-sale						6,030
Accounts payable						840
Other current liabilities						761
Deferred taxes and other noncurrent liabilities						326
Total liabilities held-for-sale						1,927
Disposal Group, Including Discontinued Operation, Additional Disclosures [Abstract]
Cash from operating activities			(601)	190
Cash from investing activities			5,051	(38)
Benefit from ceasing depreciation on assets from discontinued operations			30
Net earnings (loss) from operations of discontinued operations, net of tax	(8)	58	6	126
Income tax expense for repatriation of cash		28		28
Separation costs for professional fees and other costs, net of tax		28		50
Income tax expense for repatriation of sales proceeds and cash from discontinued operations			103
Cash payments for income taxes, professional fees and other costs paid related to discontinued businesses				57
Network Power Systems Business [Member] | Discontinued Operations, Held-for-sale or Disposed of by Sale [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from Divestiture of Business			4,000
Disposal Group, Including Discontinued Operation, Income Statement Disclosures [Abstract]
Net sales	0	1,015	630	2,063
Cost of sales	0	639	394	1,289
SG&A	0	270	180	549
Other (income) deductions, net	0	44	(461)	92
Earnings (Loss) before income taxes	0	62	517	133
Income taxes	(14)	56	540	80
Earnings (Loss), net of tax	14	6	(23)	53
Disposal Group, Including Discontinued Operation, Balance Sheet Disclosures [Abstract]
Accounts receivables						1,202
Inventories						381
Other current assets						108
Property, plant & equipment, net						352
Goodwill						2,111
Other noncurrent assets						473
Total assets held-for-sale						4,627
Accounts payable						664
Other current liabilities						620
Deferred taxes and other noncurrent liabilities						227
Total liabilities held-for-sale						1,511
Disposal Group, Including Discontinued Operation, Additional Disclosures [Abstract]
Cash from operating activities			(572)	163
Cash from investing activities			5,063	(15)
Gain on sale of business, net of tax			100
Gain on sale of business, pretax			465
Power Generation, Motors and Drives Business [Member] | Discontinued Operations, Held-for-sale or Disposed of by Sale [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Agreed-Upon Purchase Price of Business			1,200
Disposal Group, Including Discontinued Operation, Income Statement Disclosures [Abstract]
Net sales	97	341	407	679
Cost of sales	75	263	307	524
SG&A	21	71	83	137
Other (income) deductions, net	4	11	44	23
Earnings (Loss) before income taxes	(3)	(4)	(27)	(5)
Income taxes	95	0	89	0
Earnings (Loss), net of tax	(98)	$ (4)	(116)	(5)
Disposal Group, Including Discontinued Operation, Balance Sheet Disclosures [Abstract]
Accounts receivables						290
Inventories						197
Other current assets						22
Property, plant & equipment, net						259
Goodwill						580
Other noncurrent assets						55
Total assets held-for-sale						1,403
Accounts payable						176
Other current liabilities						141
Deferred taxes and other noncurrent liabilities						99
Total liabilities held-for-sale						$ 416
Disposal Group, Including Discontinued Operation, Additional Disclosures [Abstract]
Cash from operating activities			(29)	27
Cash from investing activities			(12)	$ (23)
Income tax expense recognized on completion of sale of business	134
Income tax benefit for planned repatriation of sales proceeds and cash from discontinued operations	41
Benefit from ceasing depreciation on assets from discontinued operations	$ 3
After tax loss on completion of sale of business			172
Loss on sale of business, pretax			$ 38
Scenario, Forecast [Member] | Combined, Network Power and Power Generation, motors and Drives Business [Member] | Discontinued Operations, Held-for-sale or Disposed of by Sale [Member]
Disposal Group, Including Discontinued Operation, Additional Disclosures [Abstract]
Cash from operating activities					$ 750