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Net financing charges includes interest expense, interest income, bank fees and amortization of debt issuance costs.

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Amount of income or loss from continuing operations before income taxes and noncontrolling interests, excluding general corporate expenses, intangible asset amortization, net financing charges, significant restructuring and impairment costs, and net mark-to-market adjustments on pension and postretirement plans.

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The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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Amount of gain (loss) from change in actuarial assumptions which (increases) decreases benefit obligation of defined benefit plan. Assumptions include, but are not limited to, interest, mortality, employee turnover, salary, and temporary deviation from substantive plan.

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Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

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Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

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Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Segment Information - Financial Information Related to Company's Reportable Segments (Detail) - USD ($) $ in Millions	3 Months Ended					9 Months Ended
	Jun. 30, 2018	Dec. 31, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Jun. 30, 2018	Jun. 30, 2017
Segment Reporting Information [Line Items]
Net sales	$ 8,120		$ 7,683			$ 23,030	$ 22,036
Segment EBITA	1,252		1,216			3,221	2,996
Corporate expenses	(141)		(172)			(434)	(605)
Amortization of intangible assets	(100)		(108)			(288)	(383)
Restructuring and impairment costs	0	$ (158)	(49)	$ (99)	$ (78)	(158)	(226)
Net mark-to-market adjustments on pension plans	0		(45)	$ 18	$ 117	0	90
Net financing charges	(101)		(124)			(332)	(376)
Income from continuing operations before income taxes	910		718			2,009	1,496
Power Solutions
Segment Reporting Information [Line Items]
Net sales	1,838		1,609			5,813	5,205
Segment EBITA	310		304			1,008	996
Building Technologies & Solutions
Segment Reporting Information [Line Items]
Net sales	6,282		6,074			17,217	16,831
Segment EBITA	942		912			2,213	2,000
Building Technologies & Solutions \| Building Solutions North America
Segment Reporting Information [Line Items]
Net sales	2,246		2,142			6,355	6,181
Segment EBITA	314		290			780	741
Building Technologies & Solutions \| Building Solutions EMEA/LA
Segment Reporting Information [Line Items]
Net sales	926		896			2,748	2,669
Segment EBITA	96		100			242	238
Building Technologies & Solutions \| Building Solutions Asia Pacific
Segment Reporting Information [Line Items]
Net sales	681		630			1,864	1,767
Segment EBITA	97		85			242	215
Building Technologies & Solutions \| Global Products
Segment Reporting Information [Line Items]
Net sales	2,429		2,406			6,250	6,214
Segment EBITA	$ 435		$ 437			$ 949	$ 806