Johnson Controls International (JCI) 10-Q 2 Aug 18 2018 Q3 Quarterly report Financial data

Document and Entity Information

Document and Entity Information	9 Months Ended
	Jun. 30, 2018shares
Document and Entity Information [Abstract]
Entity Registrant Name	JOHNSON CONTROLS INTERNATIONAL PLC
Entity Central Index Key	833,444
Current Fiscal Year End Date	--09-30
Entity Filer Category	Large Accelerated Filer
Document Type	10-Q
Document Period End Date	Jun. 30, 2018
Document Fiscal Year Focus	2,018
Document Fiscal Period Focus	Q3
Trading Symbol	JCI
Amendment Flag	false
Entity Common Stock, Shares Outstanding	924,922,181

Consolidated Statements of Fina

Consolidated Statements of Financial Position - USD ($) $ in Millions	Jun. 30, 2018	Sep. 30, 2017
Assets
Cash and cash equivalents	$ 283	$ 321
Accounts receivable - net	6,895	6,666
Inventories	3,509	3,209
Assets held for sale	12	189
Other current assets	1,766	1,907
Current assets	12,465	12,292
Property, plant and equipment - net	6,093	6,121
Goodwill	19,512	19,688
Other intangible assets - net	6,424	6,741
Investments in partially-owned affiliates	1,290	1,191
Noncurrent assets held for sale	0	1,920
Other noncurrent assets	3,622	3,931
Total assets	49,406	51,884
Liabilities and Equity
Short-term debt	1,559	1,214
Current portion of long-term debt	24	394
Accounts payable	4,410	4,271
Accrued compensation and benefits	984	1,071
Deferred revenue	1,317	1,279
Liabilities held for sale	0	72
Other current liabilities	3,007	3,553
Current liabilities	11,301	11,854
Long-term debt	10,373	11,964
Pension and postretirement benefits	777	947
Noncurrent liabilities held for sale	0	173
Other noncurrent liabilities	4,915	5,368
Long-term liabilities	16,065	18,452
Commitments and contingencies (Note 20)
Redeemable noncontrolling interests	231	211
Ordinary shares, $0.01 par value	9	9
Ordinary A shares, €1.00 par value	0	0
Preferred shares, $0.01 par value	0	0
Ordinary shares held in treasury, at cost	(1,004)	(710)
Capital in excess of par value	16,501	16,390
Retained earnings	6,075	5,231
Accumulated other comprehensive loss	(808)	(473)
Shareholders' equity attributable to Johnson Controls	20,773	20,447
Noncontrolling interests	1,036	920
Total equity	21,809	21,367
Total liabilities and equity	$ 49,406	$ 51,884

Consolidated Statements of Fin3

Consolidated Statements of Financial Position (Parenthetical)	Jun. 30, 2018€ / shares	Jun. 30, 2018$ / shares	Sep. 30, 2017€ / shares	Sep. 30, 2017$ / shares
Ordinary shares, par value		$ 0.01		$ 0.01
Preferred shares, par value		$ 0.01		$ 0.01
Common Class A [Member]
Ordinary shares, par value | € / shares	€ 1		€ 1

Consolidated Statements of Inco

Consolidated Statements of Income - USD ($) $ in Millions		3 Months Ended		9 Months Ended
		Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Net sales
Products and systems	[1]	$ 6,565	$ 6,172	$ 18,507	$ 17,526
Services	[1]	1,555	1,511	4,523	4,510
Net sales		8,120	7,683	23,030	22,036
Cost of sales
Products and systems	[1]	4,778	4,357	13,644	12,507
Services	[1]	870	895	2,525	2,703
Cost of sales		5,648	5,252	16,169	15,210
Gross profit		2,472	2,431	6,861	6,826
Selling, general and administrative expenses		(1,527)	(1,609)	(4,532)	(4,905)
Restructuring and impairment costs		0	(49)	(158)	(226)
Net financing charges		(101)	(124)	(332)	(376)
Equity income		66	69	170	177
Income from continuing operations before income taxes		910	718	2,009	1,496
Income tax provision		106	89	451	570
Income from continuing operations		804	629	1,558	926
Loss from discontinued operations, net of tax (Note 4)		0	0	0	(34)
Net income		804	629	1,558	892
Income from continuing operations attributable to noncontrolling interests		81	74	167	147
Income from discontinued operations attributable to noncontrolling interests		0	0	0	9
Net income attributable to Johnson Controls		723	555	1,391	736
Amounts attributable to Johnson Controls ordinary shareholders
Income from continuing operations		723	555	1,391	779
Loss from discontinued operations		$ 0	$ 0	$ 0	$ (43)
Earnings (loss) per share
Basic earnings per share from continuing operations		$ 0.78	$ 0.59	$ 1.50	$ 0.83
Basic loss per share from discontinued operations		0	0	0	(0.05)
Basic earnings per share	[2]	0.78	0.59	1.50	0.79
Diluted earnings per share from continuing operations		0.78	0.59	1.49	0.82
Diluted loss per share from discontinued operations		0	0	0	(0.05)
Diluted earnings per share	[2]	$ 0.78	$ 0.59	$ 1.49	$ 0.78
[1]	Products and systems consist of Building Technologies & Solutions and Power Solutions products and systems. Services are Building Technologies & Solutions technical services.
[2]	Certain items do not sum due to rounding

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Statement of Comprehensive Income [Abstract]
Net income	$ 804	$ 629	$ 1,558	$ 892
Other comprehensive income (loss), net of tax
Foreign currency translation adjustments	(614)	285	(331)	(166)
Realized and unrealized gains (losses) on derivatives	1	(9)	(10)	(13)
Realized and unrealized gains (losses) on marketable securities	0	(3)	(2)	6
Other comprehensive income (loss)	(613)	273	(343)	(173)
Total comprehensive income	191	902	1,215	719
Comprehensive income attributable to noncontrolling interests	22	89	159	140
Comprehensive income attributable to Johnson Controls	$ 169	$ 813	$ 1,056	$ 579

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Millions	9 Months Ended
	Jun. 30, 2018	Jun. 30, 2017
Operating Activities
Net income attributable to Johnson Controls	$ 1,391	$ 736
Income from continuing operations attributable to noncontrolling interests	167	147
Income from discontinued operations attributable to noncontrolling interests	0	9
Net income	1,558	892
Adjustments to reconcile net income to cash provided (used) by operating activities:
Depreciation and amortization	844	919
Pension and postretirement benefit income	(108)	(184)
Pension and postretirement contributions	(54)	(275)
Equity in earnings of partially-owned affiliates, net of dividends received	(111)	(166)
Deferred income taxes	(75)	1,056
Non-cash restructuring and impairment charges	30	70
Gain on Scott Safety business divestiture	(114)	0
Equity-based compensation	86	114
Other	(17)	3
Changes in assets and liabilities, excluding acquisitions and divestitures:
Accounts receivable	(282)	(319)
Inventories	(338)	(585)
Other assets	(64)	(258)
Restructuring reserves	(63)	22
Accounts payable and accrued liabilities	(198)	(590)
Accrued income taxes	167	(2,002)
Cash provided (used) by operating activities	1,261	(1,303)
Investing Activities
Capital expenditures	(782)	(996)
Sale of property, plant and equipment	23	23
Acquisition of businesses, net of cash acquired	(24)	(6)
Business divestitures	2,101	180
Changes in long-term investments	(14)	(33)
Cash provided (used) by investing activities	1,304	(832)
Financing Activities
Increase in short-term debt - net	350	887
Increase in long-term debt	886	1,553
Repayment of long-term debt	(2,760)	(972)
Debt financing costs	(4)	(18)
Stock repurchases	(255)	(426)
Payment of cash dividends	(714)	(469)
Proceeds from the exercise of stock options	39	130
Employee equity-based compensation withholding taxes	(39)	(34)
Change in noncontrolling interest share	15	8
Dividends paid to noncontrolling interests	(46)	(78)
Dividend from Adient spin-off	0	2,050
Cash transferred to Adient related to spin-off	0	(665)
Cash paid related to prior acquistions	0	(75)
Other	0	6
Cash provided (used) by financing activities	(2,528)	1,897
Effect of exchange rate changes on cash and cash equivalents	(84)	12
Change in cash held for sale	9	105
Decrease in cash and cash equivalents	(38)	(121)
Cash and cash equivalents at beginning of period	321	579
Cash and cash equivalents at end of period	$ 283	$ 458

Financial Statements

Financial Statements	9 Months Ended
	Jun. 30, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Financial Statements	Financial Statements The consolidated financial statements include the consolidated accounts of Johnson Controls International plc, a corporation organized under the laws of Ireland, and its subsidiaries (Johnson Controls International plc and all its subsidiaries, hereinafter collectively referred to as the "Company" or "Johnson Controls"). In the opinion of management, the accompanying unaudited consolidated financial statements contain all adjustments (which include normal recurring adjustments) necessary to state fairly the financial position, results of operations and cash flows for the periods presented. Certain information and footnote disclosures normally included in financial statements prepared in accordance with accounting principles generally accepted in the United States of America ("U.S. GAAP") have been omitted pursuant to the rules and regulations of the United States Securities and Exchange Commission ("SEC"). These consolidated financial statements should be read in conjunction with the audited financial statements and notes thereto included in the Company's Annual Report on Form 10-K for the year ended September 30, 2017 filed with the SEC on November 21, 2017. The results of operations for the three and nine month periods ended June 30, 2018 are not necessarily indicative of results for the Company’s 2018 fiscal year because of seasonal and other factors. Nature of Operations Johnson Controls International plc, headquartered in Cork, Ireland, is a global diversified technology and multi industrial leader serving a wide range of customers in more than 150 countries. The Company creates intelligent buildings, efficient energy solutions, integrated infrastructure and next generation transportation systems that work seamlessly together to deliver on the promise of smart cities and communities. The Company is committed to helping our customers win and creating greater value for all of its stakeholders through strategic focus on our buildings and energy growth platforms. In the fourth quarter of fiscal 2016, Johnson Controls, Inc. ("JCI Inc.") and Tyco International plc ("Tyco") completed their combination with JCI Inc. merging with a wholly-owned, indirect subsidiary of Tyco (the "Merger"). Following the Merger, Tyco changed its name to “Johnson Controls International plc” and JCI Inc. is a wholly-owned subsidiary of Johnson Controls International plc. The Merger was accounted for as a reverse acquisition using the acquisition method of accounting in accordance with Accounting Standards Codification ("ASC") 805, "Business Combinations." JCI Inc. was the accounting acquirer for financial reporting purposes. Accordingly, the historical consolidated financial statements of JCI Inc. for periods prior to this transaction are considered to be the historic financial statements of the Company. The Building Technologies & Solutions ("Buildings") business is a global market leader in engineering, developing, manufacturing and installing building products and systems around the world, including heating, ventilating, air-conditioning ("HVAC") equipment, HVAC controls, energy-management systems, security systems, fire detection systems and fire suppression solutions. The Buildings business further serves customers by providing technical services (in the HVAC, security and fire-protection space), energy-management consulting and data-driven solutions via its recently launch data-enabled business. Finally, the Company is a North American market leader in residential air conditioning and heating systems and a global market leader in industrial refrigeration products. The Power Solutions business is a leading global supplier of lead-acid automotive batteries for virtually every type of passenger car, light truck and utility vehicle. The Company serves both automotive original equipment manufacturers and the general vehicle battery aftermarket. The Company also supplies advanced battery technologies to power start-stop, hybrid and electric vehicles. Principles of Consolidation The consolidated financial statements include the consolidated accounts of Johnson Controls International plc and its subsidiaries that are consolidated in conformity with U.S. GAAP. All significant intercompany transactions have been eliminated. The results of companies acquired or disposed of during the year are included in the consolidated financial statements from the effective date of acquisition or up to the date of disposal. Investments in partially-owned affiliates are accounted for by the equity method when the Company’s interest exceeds 20% and the Company does not have a controlling interest. Under certain criteria as provided for in Financial Accounting Standards Board ("FASB") ASC 810, "Consolidation," the Company may consolidate a partially-owned affiliate. To determine whether to consolidate a partially-owned affiliate, the Company first determines if the entity is a variable interest entity ("VIE"). An entity is considered to be a VIE if it has one of the following characteristics: 1) the entity is thinly capitalized; 2) residual equity holders do not control the entity; 3) equity holders are shielded from economic losses or do not participate fully in the entity’s residual economics; or 4) the entity was established with non-substantive voting rights. If the entity meets one of these characteristics, the Company then determines if it is the primary beneficiary of the VIE. The party with the power to direct activities of the VIE that most significantly impact the VIE’s economic performance and the potential to absorb benefits or losses that could be significant to the VIE is considered the primary beneficiary and consolidates the VIE. If the entity is not considered a VIE, then the Company applies the voting interest model to determine whether or not the Company shall consolidate the partially-owned affiliate. Consolidated VIEs Based upon the criteria set forth in ASC 810, the Company has determined that it was not the primary beneficiary in any VIEs for the reporting period ended June 30, 2018 and that it was the primary beneficiary in one VIE for the reporting period ended September 30, 2017 , as the Company absorbed significant economics of the entity and had the power to direct the activities that are considered most significant to the entity. In fiscal 2012, a pre-existing VIE accounted for under the equity method was reorganized into three separate investments as a result of the counterparty exercising its option to put its interest to the Company. The Company acquired additional interests in two of the reorganized group entities. The reorganized group entities are considered to be VIEs as the other owner party has been provided decision making rights but does not have equity at risk. The Company was considered the primary beneficiary of one of the entities due to the Company’s power pertaining to decisions over significant activities of the entity. As such, this VIE was consolidated within the Company’s consolidated statements of financial position as of September 30, 2017. During the quarter ended December 31, 2017, certain joint venture agreements were amended, and as a result, the Company can no longer make key operating decisions considered to be most significant to the VIE. As such, the Company is no longer considered the primary beneficiary of this entity, and the Company deconsolidated the entity during the quarter ended December 31, 2017. The impact of the entity on the Company’s consolidated statements of income for the nine month periods ended June 30, 2018 and 2017 was not material. The carrying amounts and classification of assets (none of which are restricted) and liabilities included in the Company’s consolidated statements of financial position for the consolidated VIE is as follows (in millions): September 30, 2017 Current assets $ 2 Noncurrent assets 53 Total assets $ 55 Current liabilities $ 6 Noncurrent liabilities 42 Total liabilities $ 48 The Company did not have a significant variable interest in any other consolidated VIEs for the presented reporting periods. Nonconsolidated VIEs As mentioned previously within the "Consolidated VIEs" section above, in fisca1 2012, a pre-existing VIE was reorganized into three separate investments as a result of the counterparty exercising its option to put its interest to the Company. The reorganized group entities are considered to be VIEs as the other owner party has been provided decision making rights but does not have equity at risk. The VIEs are named as co-obligors under a third party debt agreement in the amount of $157 million , maturing in fiscal 2020, under which a VIE could become subject to paying more than its allocated share of the third party debt in the event of bankruptcy of one or more of the other co-obligors. The other co-obligors, all related parties in which the Company is an equity investor, consist of the remaining group entities involved in the reorganization. As part of the overall reorganization transaction, the Company has also provided financial support to the group entities in the form of loans totaling $38 million , which are subordinate to the third party debt agreement. The Company is a significant customer of certain co-obligors, resulting in a remote possibility of loss. Additionally, the Company is subject to a floor guaranty expiring in fiscal 2022; in the event that the other owner party no longer owns any part of the group entities due to sale or transfer, the Company has guaranteed that the proceeds received from the sale or transfer will not be less than $25 million . The Company has partnered with the group entities to design and manufacture battery components for the Power Solutions business. The Company is not considered to be the primary beneficiary of three of the entities as of June 30, 2018 and two of the entities as of September 30, 2017 , as the Company cannot make key operating decisions considered to be most significant to the VIEs. Therefore, the entities are accounted for under the equity method of accounting as the Company’s interest exceeds 20% and the Company does not have a controlling interest. The Company’s maximum exposure to loss includes the partially-owned affiliate investment balances of $42 million and $65 million at June 30, 2018 and September 30, 2017 , respectively, as well as the subordinated loan from the Company, third party debt agreement and floor guaranty mentioned above. Current liabilities due to the VIEs are not material and represent normal course of business trade payables for all presented periods. The Company did not have a significant variable interest in any other unconsolidated VIEs for the presented reporting periods. Restricted Cash At June 30, 2018 , the Company held restricted cash of approximately $19 million , of which $10 million was recorded within other current assets in the consolidated statements of financial position and $9 million was recorded within other noncurrent assets in the consolidated statements of financial position. At September 30, 2017 , the Company held restricted cash of approximately $31 million , of which $22 million was recorded within other current assets in the consolidated statements of financial position and $9 million was recorded within other noncurrent assets in the consolidated statements of financial position. These amounts were primarily related to cash restricted for payment of asbestos liabilities. Retrospective Changes Effective July 1, 2017, the Company reorganized the reportable segments within its Building Technologies & Solutions business to align with its new management reporting structure and business activities. Prior to this reorganization, Building Technologies & Solutions was comprised of five reportable segments for financial reporting purposes: Systems and Service North America, Products North America, Asia, Rest of World and Tyco. As a result of this change, Building Technologies & Solutions is now comprised of four reportable segments for financial reporting purposes: Building Solutions North America, Building Solutions EMEA/LA, Building Solutions Asia Pacific and Global Products. Refer to Note 18, “Segment Information,” of the notes to consolidated financial statements for further information. The net sales and cost of sales split of products and systems versus services in the consolidated statements of income has also been revised for the Building Technologies & Solutions reorganization. In March 2016, the FASB issued Accounting Standards Update ("ASU") No. 2016-09, "Compensation - Stock Compensation (Topic 718): Improvements to Employee Share-Based Payment Accounting." During the quarter ended December 31, 2017, the Company adopted ASU No. 2016-09. As a result, employee withholding taxes paid to taxing authorities for equity-based compensation transactions, previously classified as cash flows from operating activities, were reclassified to financing activities in the consolidated statements of cash flows for the nine months ended June 30, 2017. Refer to Note 2, "New Accounting Standards," of the notes to consolidated financial statements for further information.

New Accounting Standards

New Accounting Standards	9 Months Ended
	Jun. 30, 2018
New Accounting Pronouncements and Changes in Accounting Principles [Abstract]
New Accounting Standards	New Accounting Standards Recently Adopted Accounting Pronouncements In March 2018, the FASB issued ASU No. 2018-05, "Income Taxes (Topic 740): Amendments to SEC Paragraphs Pursuant to SEC Staff Accounting Bulletin No. 118" to add various SEC paragraphs pursuant to the issuance of SEC Staff Accounting Bulletin No. 118 ("SAB 118") to ASC 740 "Income Taxes." SAB 118 was issued by the SEC in December 2017 to provide immediate guidance for accounting implications of U.S. tax reform under the "Tax Cuts and Jobs Act" in the period of enactment. SAB 118 provides for a provisional one year measurement period for entities to finalize their accounting for certain income tax effects related to the "Tax Cuts and Jobs Act." The Company applied this guidance to its consolidated financial statements and related disclosures beginning in the quarter ended December 31, 2017. Refer to Note 9, "Income Taxes," of the notes to consolidated financial statements for further information. In August 2017, the FASB issued ASU No. 2017-12, "Derivatives and Hedging (Topic 815): Targeted Improvements to Accounting for Hedging Activities." The ASU more closely aligns the results of hedge accounting with risk management activities through amendments to the designation and measurement guidance to better reflect a Company's hedging strategy and effectiveness. During the quarter ended December 31, 2017, the Company early adopted ASU 2017-12. The adoption of this guidance did not have a material impact on the Company's consolidated financial statements. In March 2016, the FASB issued ASU No. 2016-09, "Compensation - Stock Compensation (Topic 718): Improvements to Employee Share-Based Payment Accounting." ASU No. 2016-09 impacts certain aspects of the accounting for share-based payment transactions, including income tax consequences, classification of awards as either equity or liabilities, and classification on the statements of cash flows. During the quarter ended December 31, 2017, the Company adopted ASU No. 2016-09. As a result, the Company recognized deferred tax assets of $179 million in the consolidated statements of financial position related to certain operating loss carryforwards resulting from the exercise of employee stock options and vested restricted stock on a modified retrospective basis through a cumulative-effect adjustment to retained earnings as of October 1, 2017. Additionally, employee withholding taxes paid to taxing authorities for equity-based compensation transactions, previously classified as cash flows from operating activities, were reclassified to financing activities in the consolidated statements of cash flows for the nine months ended June 30, 2017 for comparative purposes. The remaining provisions of ASU No. 2016-09 did not have a material impact on the Company's consolidated financial statements. Recently Issued Accounting Pronouncements In November 2016, the FASB issued ASU No. 2016-18, "Statement of Cash Flows (Topic 230): Restricted Cash (a consensus of the FASB Emerging Issues Task Force)." The ASU requires amounts generally described as restricted cash and restricted cash equivalents to be included with cash and cash equivalents when reconciling the beginning-of-period and end-of-period total amounts shown on the statement of cash flows. The guidance will be effective for the Company for the quarter ending December 31, 2018, with early adoption permitted. The amendments in this update should be applied retrospectively to all periods presented. The impact of this guidance for the Company will depend on the levels of restricted cash balances in the periods presented. In October 2016, the FASB issued ASU No. 2016-16, "Accounting for Income Taxes: Intra-Entity Asset Transfers of Assets Other than Inventory." The ASU requires the tax effects of all intra-entity sales of assets other than inventory to be recognized in the period in which the transaction occurs. The guidance will be effective for the Company for the quarter ending December 31, 2018, with early adoption permitted but only in the first interim period of a fiscal year. The changes are required to be applied by means of a cumulative-effect adjustment recorded in retained earnings as of the beginning of the fiscal year of adoption. The Company is currently assessing the impact adoption of this guidance will have on its consolidated financial statements. In August 2016, the FASB issued ASU No. 2016-15, "Statement of Cash Flows (Topic 230): Classification of Certain Cash Receipts and Cash Payments." ASU No. 2016-15 provides clarification guidance on eight specific cash flow presentation issues in order to reduce the diversity in practice. ASU No. 2016-15 will be effective for the Company for the quarter ending December 31, 2018, with early adoption permitted. The guidance should be applied retrospectively to all periods presented, unless deemed impracticable, in which case prospective application is permitted. The Company is currently assessing the impact adoption of this guidance will have on its consolidated financial statements. In February 2016, the FASB issued ASU No. 2016-02, "Leases (Topic 842)." ASU No. 2016-02 requires recognition of operating leases as lease assets and liabilities on the balance sheet, and disclosure of key information about leasing arrangements. The original standard was effective retrospectively for the Company for the quarter ending December 31, 2019 with early adoption permitted; however in July 2018 the FASB issued ASU No. 2018-11, "Leases (Topic 842): Targeted Improvements," which provides an additional transition method that permits changes to be applied by means of a cumulative-effect adjustment recorded in retained earnings as of the beginning of the fiscal year of adoption. The Company is currently assessing the impact adoption of this guidance will have on its consolidated financial statements. The Company has started the assessment process by evaluating the population of leases under the revised definition of what qualifies as a leased asset. The Company is the lessee under various agreements for facilities and equipment that are currently accounted for as operating leases. The new guidance will require the Company to record operating leases on the balance sheet with a right-of-use asset and corresponding liability for future payment obligations. Additionally in January 2018, the FASB issued ASU No. 2018-01, "Leases (Topic 842): Land Easement Practical Expedient for Transition to Topic 842," which provides an optional transition practical expedient for existing or expired land easements that were not previously recorded as leases. The Company expects the new guidance will have a material impact on its consolidated statements of financial position for the addition of right-of-use assets and lease liabilities, but the Company does not expect it to have a material impact on its consolidated statements of income and its consolidated statements of cash flows. In January 2016, the FASB issued ASU No. 2016-01, "Financial Instruments - Overall (Subtopic 825-10): Recognition and Measurement of Financial Assets and Financial Liabilities." ASU No. 2016-01 amends certain aspects of recognition, measurement, presentation and disclosure of financial instruments, including marketable securities. ASU No. 2016-01 will be effective for the Company for the quarter ending December 31, 2018, and early adoption is not permitted, with certain exceptions. The changes are required to be applied by means of a cumulative-effect adjustment on the balance sheet as of the beginning of the fiscal year of adoption. Additionally in February 2018, the FASB issued ASU No. 2018-03, "Technical Corrections and Improvements to Financial Instruments—Overall (Subtopic 825-10): Recognition and Measurement of Financial Assets and Financial Liabilities," which provides additional clarification on certain topics addressed in ASU No. 2016-01. ASU No. 2018-01 will be effective for the Company when ASU No. 2016-01 is adopted. The impact of this guidance for the Company will depend on the magnitude of the unrealized gains and losses on the Company's marketable securities investments. In May 2014, the FASB issued ASU No. 2014-09, "Revenue from Contracts with Customers (Topic 606)." ASU No. 2014-09 clarifies the principles for recognizing revenue when an entity either enters into a contract with customers to transfer goods or services or enters into a contract for the transfer of non-financial assets. The original standard was effective retrospectively for the Company for the quarter ending December 31, 2017; however in August 2015, the FASB issued ASU No. 2015-14, "Revenue from Contracts with Customers (Topic 606): Deferral of the Effective Date," which defers the effective date of ASU No. 2014-09 by one-year for all entities. The new standard will become effective retrospectively for the Company for the quarter ending December 31, 2018, with early adoption permitted, but not before the original effective date. Additionally, in March 2016, the FASB issued ASU No. 2016-08, "Revenue from Contracts with Customers (Topic 606): Principal versus Agent Considerations (Reporting Revenue Gross versus Net)," in April 2016, the FASB issued ASU No. 2016-10, "Revenue from Contracts with Customers (Topic 606): Identifying Performance Obligations and Licensing," in May 2016, the FASB issued ASU No. 2016-12, "Revenue from Contracts with Customers (Topic 606): Narrow-Scope Improvements and Practical Expedients," and in December 2016, the FASB issued ASU No. 2016-20, "Technical Corrections and Improvements to Topic 606, Revenue from Contracts with Customers," all of which provide additional clarification on certain topics addressed in ASU No. 2014-09. ASU No. 2016-08, ASU No. 2016-10, ASU No. 2016-12 and ASU No. 2016-20 follow the same implementation guidelines as ASU No. 2014-09 and ASU No. 2015-14. The Company has elected to adopt the new revenue guidance as of October 1, 2018 using the modified retrospective approach. Based on the Company’s initial evaluation of current contracts and revenue streams, revenue recognition is expected to be mostly consistent under both the current and new standard, with the exception of Power Solutions business. Within the Power Solutions business, certain customers return battery cores which will be included in the transaction price as noncash consideration under the new revenue standard. This change is expected to result in an increase to annual Power Solutions revenue of approximately 10% - 15% and an immaterial impact to gross profit. The Company does not expect the new revenue standard will have a material impact on its consolidated statements of financial position and its consolidated statements of cash flows. Other recently issued accounting pronouncements are not expected to have a material impact on the Company's consolidated financial statements.

Acquisitions and Divestitures

Acquisitions and Divestitures	9 Months Ended
	Jun. 30, 2018
Business Combinations [Abstract]
Acquisition and Divestitures	Acquisitions and Divestitures During the first nine months of fiscal 2018, the Company completed certain acquisitions for a combined purchase price of $24 million , all of which was paid as of June 30, 2018. The acquisitions in the aggregate were not material to the Company’s consolidated financial statements. In connection with the acquisitions, the Company recorded goodwill of $12 million within the Global Products segment. In the second quarter of fiscal 2018, the Company completed the sale of a certain Global Products business. The selling price was $103 million , all of which was received in the three months ended March 31, 2018. In connection with the sale, the Company reduced goodwill by $20 million and realized an insignificant gain. The divestiture was not material to the Company's consolidated financial statements. In the first quarter of fiscal 2018, the Company completed the sale of its Scott Safety business to 3M Company. The selling price, net of cash divested, was $2.0 billion , all of which was received as of December 31, 2017. In connection with the sale, the Company recorded a pre-tax gain of $114 million within selling, general and administrative expenses in the consolidated statements of income and reduced goodwill in assets held for sale by $1.2 billion . The gain, net of tax, recorded was $84 million . Net cash proceeds from the transaction of approximately $1.9 billion were used to repay a significant portion of the Tyco International Holding S.a.r.L.'s ("TSarl") $4.0 billion of merger-related debt. The Scott Safety business is included in the Global Products segment and was reported within assets and liabilities held for sale in the consolidated statements of financial position as of September 30, 2017. Refer to Note 4, "Discontinued Operations," of the notes to consolidated financial statements for further disclosure related to the Company's net assets held for sale. In the first nine months of fiscal 2017, the Company completed three acquisitions for a combined purchase price, net of cash acquired, of $9 million , $6 million of which was paid in the nine months ended June 30, 2017. The acquisitions in the aggregate were not material to the Company’s consolidated financial statements. In the second quarter of fiscal 2017, the Company completed the sale of its ADT security business in South Africa within the Building Solutions EMEA/LA segment. The selling price, net of cash divested, was $129 million , all of which was received in the nine months ended June 30, 2017. In connection with the sale, the Company reduced goodwill in assets held for sale by $92 million . The divestiture was not material to the Company's consolidated financial statements. In the first nine months of fiscal 2017, the Company completed one additional divestiture for a sales price of $4 million , all of which was received in the nine months ended June 30, 2017. The divestiture decreased the Company's ownership from a controlling to noncontrolling interest, and as a result, the Company deconsolidated cash of $5 million . The divestiture was not material to the Company's consolidated financial statements. In the first nine months of fiscal 2017, the Company received $52 million in net cash proceeds related to prior year business divestitures and paid $75 million related to prior year business acquisitions.

Discontinued Operations (Notes)

Discontinued Operations (Notes)	9 Months Ended
	Jun. 30, 2018
Discontinued Operations [Abstract]
Discontinued Operations	Discontinued Operations On October 31, 2016, the Company completed the spin-off of its Automotive Experience business by way of the transfer of the Automotive Experience business from Johnson Controls to Adient plc and the issuance of ordinary shares of Adient directly to holders of Johnson Controls ordinary shares on a pro rata basis. Prior to the open of business on October 31, 2016, each of the Company's shareholders received one ordinary share of Adient plc for every 10 ordinary shares of Johnson Controls held as of the close of business on October 19, 2016, the record date for the distribution. Company shareholders received cash in lieu of fractional shares of Adient, if any. Following the separation and distribution, Adient plc is now an independent public company trading on the New York Stock Exchange ("NYSE") under the symbol "ADNT." The Company did not retain any equity interest in Adient plc. Adient’s historical financial results are reflected in the Company’s consolidated financial statements as a discontinued operation. The Company did not allocate any general corporate overhead to discontinued operations. The following table summarizes the results of Adient, reclassified as discontinued operations for the nine month period ended June 30, 2017 (in millions). As the Adient spin-off occurred on October 31, 2016, there is only one month of Adient results included in the nine month period ended June 30, 2017 . Nine Months Ended 2017 Net sales $ 1,434 Income from discontinued operations before income taxes 1 Provision for income taxes on discontinued operations 35 Income from discontinued operations attributable to noncontrolling interests, net of tax 9 Loss from discontinued operations $ (43 ) For the nine months ended June 30, 2017 , the income from discontinued operations before income taxes included separation costs of $79 million . For the nine months ended June 30, 2017 , the effective tax rate was more than the U.S. federal statutory rate of 35% primarily due to the tax impacts of separation costs and Adient spin-off related tax expense, partially offset by non-U.S. tax rate differentials. The following table summarizes depreciation and amortization, capital expenditures, and significant operating and investing noncash items related to Adient for the nine month period ended June 30, 2017 (in millions): Nine Months Ended 2017 Depreciation and amortization $ 29 Equity in earnings of partially-owned affiliates (31 ) Deferred income taxes 562 Equity-based compensation 1 Accrued income taxes (808 ) Capital expenditures (91 ) Assets and Liabilities Held for Sale During the second quarter of fiscal 2017, the Company signed a definitive agreement to sell its Scott Safety business of the Global Products segment to 3M Company. The transaction closed on October 4, 2017. The assets and liabilities of this business are presented as held for sale in the consolidated statements of financial position as of September 30, 2017. The business did not meet the criteria to be classified as a discontinued operation as the divestiture of the Scott Safety business did not have a major effect on the Company’s operations and financial results. The following table summarizes the carrying value of the Scott Safety assets and liabilities held for sale at September 30, 2017 (in millions): September 30, 2017 Cash $ 9 Accounts receivable - net 100 Inventories 75 Other current assets 5 Assets held for sale $ 189 Property, plant and equipment - net $ 79 Goodwill 1,248 Other intangible assets - net 592 Other noncurrent assets 1 Noncurrent assets held for sale $ 1,920 Accounts payable $ 37 Accrued compensation and benefits 10 Other current liabilities 25 Liabilities held for sale $ 72 Other noncurrent liabilities $ 173 Noncurrent liabilities held for sale $ 173 At June 30, 2018, $12 million of certain Corporate assets were classified as held for sale.

Percentage-of-Completion Contra

Percentage-of-Completion Contracts	9 Months Ended
	Jun. 30, 2018
Disclosure Percentage Of Completion Contracts Additional Information [Abstract]
Percentage-of-Completion Contracts	Percentage-of-Completion Contracts The Building Technologies & Solutions business records certain long-term contracts under the percentage-of-completion method of accounting. Under this method, sales and gross profit are recognized as work is performed based on the relationship between actual costs incurred and total estimated costs at completion. The Company records costs and earnings in excess of billings on uncompleted contracts primarily within accounts receivable - net and billings in excess of costs and earnings on uncompleted contracts primarily within deferred revenue in the consolidated statements of financial position. Costs and earnings in excess of billings related to these contracts were $1,025 million and $908 million at June 30, 2018 and September 30, 2017 , respectively. Billings in excess of costs and earnings related to these contracts were $545 million and $451 million at June 30, 2018 and September 30, 2017 , respectively.

Inventories

Inventories	9 Months Ended
	Jun. 30, 2018
Inventory Disclosure [Abstract]
Inventories	Inventories Inventories consisted of the following (in millions): June 30, 2018 September 30, 2017 Raw materials and supplies $ 953 $ 919 Work-in-process 578 567 Finished goods 1,978 1,723 Inventories $ 3,509 $ 3,209

Goodwill and Other Intangible A

Goodwill and Other Intangible Assets (Notes)	9 Months Ended
	Jun. 30, 2018
Goodwill and Intangible Assets Disclosure [Abstract]
GOODWILL AND OTHER INTANGIBLE ASSETS	Goodwill and Other Intangible Assets The changes in the carrying amount of goodwill in each of the Company’s reportable segments for the nine month period ended June 30, 2018 were as follows (in millions): Business Acquisitions Business Divestitures Currency Translation and Other September 30, June 30, 2017 2018 Building Technologies & Solutions Building Solutions North America $ 9,637 $ — $ — $ (45 ) $ 9,592 Building Solutions EMEA/LA 2,012 — — (53 ) 1,959 Building Solutions Asia Pacific 1,255 — — 2 1,257 Global Products 5,687 12 (20 ) (70 ) 5,609 Power Solutions 1,097 — — (2 ) 1,095 Total $ 19,688 $ 12 $ (20 ) $ (168 ) $ 19,512 At September 30, 2017 , accumulated goodwill impairment charges included $47 million related to the Building Solutions EMEA/LA - Latin America reporting unit. The Company’s other intangible assets, primarily from business acquisitions valued based on independent appraisals, consisted of (in millions): June 30, 2018 September 30, 2017 Gross Carrying Amount Accumulated Amortization Net Gross Carrying Amount Accumulated Amortization Net Amortized intangible assets Technology $ 1,326 $ (233 ) $ 1,093 $ 1,328 $ (137 ) $ 1,191 Customer relationships 3,091 (605 ) 2,486 3,168 (486 ) 2,682 Miscellaneous 457 (181 ) 276 389 (147 ) 242 Total amortized intangible assets 4,874 (1,019 ) 3,855 4,885 (770 ) 4,115 Unamortized intangible assets Trademarks/trade names 2,447 — 2,447 2,483 — 2,483 Miscellaneous 122 — 122 143 — 143 2,569 — 2,569 2,626 — 2,626 Total intangible assets $ 7,443 $ (1,019 ) $ 6,424 $ 7,511 $ (770 ) $ 6,741 Amortization of other intangible assets included within continuing operations for the three month periods ended June 30, 2018 and 2017 was $100 million and $108 million , respectively. Amortization of other intangible assets included within continuing operations for the nine month periods ended June 30, 2018 and 2017 was $288 million and $383 million , respectively. Excluding the impact of any future acquisitions, the Company anticipates amortization for fiscal 2019, 2020, 2021, 2022 and 2023 will be approximately $388 million , $380 million , $371 million , $365 million and $344 million per year, respectively.

Significant Restructuring Costs

Significant Restructuring Costs	9 Months Ended
	Jun. 30, 2018
Restructuring Charges [Abstract]
Significant Restructuring and Impairment Costs	Significant Restructuring and Impairment Costs To better align its resources with its growth strategies and reduce the cost structure of its global operations in certain underlying markets, the Company commits to restructuring plans as necessary. In fiscal 2018, the Company committed to a significant restructuring plan (2018 Plan) and recorded $158 million of restructuring and impairment costs in the consolidated statements of income. This was the total amount incurred to date and the total amount expected to be incurred for this restructuring plan. The restructuring actions related to cost reduction initiatives in the Company’s Building Technologies & Solutions and Power Solutions businesses and at Corporate. The costs consist primarily of workforce reductions, plant closures and asset impairments. Of the restructuring and impairment costs recorded, $76 million related to the Global Products segment, $32 million related to the Building Solutions EMEA/LA segment, $24 million related to Corporate, $14 million related to the Building Solutions Asia Pacific segment, $8 million related to the Building Solutions North America segment and $4 million related to the Power Solutions segment. The restructuring actions are expected to be substantially complete in 2020. The following table summarizes the changes in the Company’s 2018 Plan reserve, included within other current liabilities in the consolidated statements of financial position (in millions): Employee Severance and Termination Benefits Long-Lived Asset Impairments Other Total Original reserve $ 125 $ 30 $ 3 $ 158 Utilized—noncash — (30 ) — (30 ) Balance at December 31, 2017 $ 125 $ — $ 3 $ 128 Utilized—cash (8 ) — (1 ) (9 ) Balance at March 31, 2018 $ 117 $ — $ 2 $ 119 Utilized—cash (12 ) — (1 ) (13 ) Balance at June 30, 2018 $ 105 $ — $ 1 $ 106 In fiscal 2017, the Company committed to a significant restructuring plan (2017 Plan) and recorded $367 million of restructuring and impairment costs in the consolidated statements of income. This was the total amount incurred to date and the total amount expected to be incurred for this restructuring plan. The restructuring actions related to cost reduction initiatives in the Company’s Building Technologies & Solutions and Power Solutions businesses and at Corporate. The costs consist primarily of workforce reductions, plant closures and asset impairments. Of the restructuring and impairment costs recorded, $166 million related to Corporate, $74 million related to the Building Solutions EMEA/LA segment, $59 million related to the Building Solutions North America segment, $32 million related to the Global Products segment, $20 million related to the Power Solutions segment and $16 million related to the Building Solutions Asia Pacific segment. The restructuring actions are expected to be substantially complete in 2018. The following table summarizes the changes in the Company’s 2017 Plan reserve, included within other current liabilities in the consolidated statements of financial position (in millions): Employee Severance and Termination Benefits Long-Lived Asset Impairments Other Currency Total Original reserve $ 276 $ 77 $ 14 $ — $ 367 Utilized—cash (75 ) — — — (75 ) Utilized—noncash — (77 ) (1 ) — (78 ) Adjustment to restructuring reserves 25 — — — 25 Balance at September 30, 2017 $ 226 $ — $ 13 $ — $ 239 Utilized—cash (142 ) — (4 ) — (146 ) Utilized—noncash — — — (1 ) (1 ) Balance at June 30, 2018 $ 84 $ — $ 9 $ (1 ) $ 92 In fiscal 2016, the Company committed to a significant restructuring plan (2016 Plan) and recorded $288 million of restructuring and impairment costs in the consolidated statements of income. This was the total amount incurred to date and the total amount expected to be incurred for this restructuring plan. The restructuring actions related to cost reduction initiatives in the Company’s Building Technologies & Solutions and Power Solutions businesses and at Corporate. The costs consist primarily of workforce reductions, plant closures, asset impairments and change-in-control payments. Of the restructuring and impairment costs recorded, $161 million related to Corporate, $66 million related to the Power Solutions segment, $44 million related to the Global Products segment and $17 million related to the Building Solutions EMEA/LA segment. The restructuring actions are expected to be substantially complete in 2018. Included in the reserve is $56 million of committed restructuring actions taken by Tyco for liabilities assumed as part of the Tyco acquisition. Additionally, the Company recorded $332 million of restructuring and impairment costs within discontinued operations related to Adient in fiscal 2016. The following table summarizes the changes in the Company’s 2016 Plan reserve, included within other current liabilities in the consolidated statements of financial position (in millions): Employee Severance and Termination Benefits Long-Lived Asset Impairments Other Currency Total Original reserve $ 368 $ 190 $ 62 $ — $ 620 Acquired Tyco restructuring reserves 78 — — — 78 Utilized—cash (32 ) — — — (32 ) Utilized—noncash — (190 ) (32 ) 1 (221 ) Balance at September 30, 2016 $ 414 $ — $ 30 $ 1 $ 445 Adient spin-off impact (194 ) — (22 ) — (216 ) Utilized—cash (86 ) — (2 ) — (88 ) Utilized—noncash — — — 1 1 Adjustment to restructuring reserves (25 ) — — — (25 ) Transfer to liabilities held for sale (3 ) — — — (3 ) Adjustment to acquired Tyco restructuring reserves (22 ) — — — (22 ) Balance at September 30, 2017 $ 84 $ — $ 6 $ 2 $ 92 Utilized—cash (16 ) — (2 ) — (18 ) Balance at June 30, 2018 $ 68 $ — $ 4 $ 2 $ 74 The Company's fiscal 2018, 2017 and 2016 restructuring plans included workforce reductions of approximately 9,200 employees ( 7,300 for the Building Technologies & Solutions business, 1,700 for Corporate and 200 for Power Solutions). Restructuring charges associated with employee severance and termination benefits are paid over the severance period granted to each employee or on a lump sum basis in accordance with individual severance agreements. As of June 30, 2018 , approximately 4,300 of the employees have been separated from the Company pursuant to the restructuring plans. In addition, the restructuring plans included eleven plant closures in the Building Technologies & Solutions business. As of June 30, 2018 , six of the eleven plants have been closed. Company management closely monitors its overall cost structure and continually analyzes each of its businesses for opportunities to consolidate current operations, improve operating efficiencies and locate facilities in close proximity to customers. This ongoing analysis includes a review of its manufacturing, engineering and purchasing operations, as well as the overall global footprint for all its businesses.

Income Taxes

Income Taxes	9 Months Ended
	Jun. 30, 2018
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes In calculating the provision for income taxes, the Company uses an estimate of the annual effective tax rate based upon the facts and circumstances known at each interim period. On a quarterly basis, the actual effective tax rate is adjusted, as appropriate, based upon changed facts and circumstances, if any, as compared to those forecasted at the beginning of the fiscal year and each interim period thereafter. The statutory tax rate in Ireland is being used as a comparison since the Company is domiciled in Ireland. For the three months ended June 30, 2018 and 2017, the Company's effective tax rate was consistent with the statutory tax rate of 12.5% . For the nine months ended June 30, 2018, the Company's effective tax rate was 22% and was higher than the statutory tax rate of 12.5% primarily due to the discrete net impacts of U.S. Tax Reform, final income tax effects of the completed divestiture of the Scott Safety business and tax rate differentials, partially offset by the benefits of continuing global tax planning initiatives and tax audit closures. For the nine months ended June 30, 2017, the Company's effective tax rate was 38% and was higher than the statutory tax rate of 12.5% primarily due to the establishment of a deferred tax liability on the outside basis difference of the Company's investment in certain subsidiaries related to the divestiture of the Scott Safety business, the income tax effects of pension mark-to-market gains and tax rate differentials, partially offset by the jurisdictional mix of significant restructuring and impairment costs, Tyco Merger transaction and integration costs, purchase accounting adjustments, a tax benefit due to changes in entity tax status and the benefits of continuing global tax planning initiatives. Valuation Allowance The Company reviews the realizability of its deferred tax assets on a quarterly basis, or whenever events or changes in circumstances indicate that a review is required. In determining the requirement for a valuation allowance, the historical and projected financial results of the legal entity or consolidated group recording the net deferred tax asset are considered, along with any other positive or negative evidence. Since future financial results may differ from previous estimates, periodic adjustments to the Company’s valuation allowances may be necessary. Uncertain Tax Positions At September 30, 2017 , the Company had gross tax effected unrecognized tax benefits of $2,173 million , of which $2,047 million , if recognized, would impact the effective tax rate. Total net accrued interest at September 30, 2017 was approximately $99 million (net of tax benefit). The interest and penalties accrued during the nine months ended June 30, 2018 and 2017 were immaterial. The Company recognizes interest and penalties related to unrecognized tax benefits as a component of income tax expense. In the first quarter of fiscal 2018, tax audit resolutions resulted in a $25 million net benefit to income tax expense. In the U.S., fiscal years 2015 through 2016 are currently under exam by the Internal Revenue Service ("IRS"). Additionally, the Company is currently under exam in the following major non-U.S. jurisdictions: Tax Jurisdiction Tax Years Covered Belgium 2015 - 2016 China 2008 - 2016 France 2010 - 2012; 2015 - 2016 Germany 2007 - 2015 Spain 2010 - 2012 Switzerland 2011 - 2014 United Kingdom 2011 - 2015 Impacts of Tax Legislation On December 22, 2017, the “Tax Cuts and Jobs Act” (H.R. 1) was enacted and significantly revises U.S. corporate income tax by, among other things, lowering corporate income tax rates, imposing a one-time transition tax on deemed repatriated earnings of non-U.S. subsidiaries, and implementing a territorial tax system and various base erosion minimum tax provisions. In the first quarter of fiscal 2018, as a result of the enacted legislation, the Company recorded a discrete non-cash tax benefit of $101 million due to the remeasurement of U.S. deferred tax assets and liabilities. The Company remeasured certain deferred tax assets and liabilities based on the rates at which they are expected to reverse in the future, which is generally 21% or the blended fiscal 2018 rate of 24.5% . This tax benefit is provisional as the Company is still analyzing certain aspects of the legislation and refining calculations, which could potentially materially affect the measurement of these amounts or give rise to new deferred tax amounts. In the first quarter of fiscal 2018, the Company also recorded a discrete tax charge of $305 million due to the one-time transition tax on deemed repatriated earnings of certain non-U.S. subsidiaries. This charge is inclusive of relevant non-U.S. withholding taxes and U.S. state income tax on the portion of the earnings expected to be repatriated. This one-time transition tax is based on the Company’s post-1986 earnings and profits (“E&P”) not previously subjected to U.S. taxation. This tax charge is provisional as the Company has not yet finally determined its post-1986 non-U.S. E&P. Further, the transition tax is based in part on the amount of those earnings held in cash and other specified assets. Given the varying tax rates ( 15.5% on cash and 8% on other property), this amount may change when the Company completes the calculation of post-1986 non-U.S. E&P previously deferred from U.S. federal taxation and concludes on the amounts held in cash versus other specified assets. Various impacts of the enacted legislation are still being evaluated by the Company and may materially differ from the estimated impacts recognized in the first quarter of fiscal 2018 due to future treasury regulations, tax law technical corrections, and other potential guidance, notices, rulings, refined computations, actions the Company may take as a result of the tax legislation, and other items. The SEC has issued rules that allow for a measurement period of up to one year after the enactment date of the legislation to finalize the recording of the related tax impacts. On October 13, 2016, the U.S. Treasury and the IRS released final and temporary Section 385 regulations. These regulations address whether certain instruments between related parties are treated as debt or equity. The Company does not expect that the regulations will have a material impact on its consolidated financial statements. During the nine months ended June 30, 2018 and 2017 , other tax legislation was adopted in various jurisdictions. These law changes did not have a material impact on the Company's consolidated financial statements. Other Tax Matters In the third quarter of fiscal 2018, the Company recorded $51 million of transaction and integration costs. These costs generated a $6 million tax benefit which reflects the Company's current tax position in these jurisdictions. In the second quarter of fiscal 2018, the Company recorded $64 million of transaction and integration costs. These costs generated a $9 million tax benefit which reflects the Company’s current tax position in these jurisdictions. In the first quarter of fiscal 2018, the Company completed the sale of its Scott Safety business to 3M Company. Refer to Note 3, "Acquisitions and Divestitures," of the notes to consolidated financial statements for additional information. In connection with the sale, the Company recorded a pre-tax gain of $114 million and income tax expense of $30 million . In the first quarter of fiscal 2018, the Company recorded $50 million of transaction and integration costs. These costs generated a $7 million tax benefit which reflects the Company’s current tax position in these jurisdictions. In the first quarter of fiscal 2018, the Company recorded $158 million of significant restructuring and impairment costs. Refer to Note 8, "Significant Restructuring and Impairment Costs," of the notes to consolidated financial statements for additional information. The restructuring costs generated a $24 million tax benefit, which reflects the Company’s current tax position in these jurisdictions. In the third quarter of fiscal 2017, the Company recorded $70 million of transaction and integration costs which generated an $11 million tax benefit. In the third quarter of fiscal 2017, the Company recorded pension mark-to-market losses of $45 million which generated an $18 million tax benefit. In the third quarter of fiscal 2017, the Company recorded $49 million of significant restructuring and impairment costs. Refer to Note 8, "Significant Restructuring and Impairment Costs," of the notes to consolidated financial statements for additional information. The restructuring costs generated a $15 million tax benefit. In the second quarter of fiscal 2017, the Company recorded a discrete non-cash tax charge of $457 million related to establishment of a deferred tax liability on the outside basis difference of the Company's investment in certain subsidiaries of the Scott Safety business. In the second quarter of fiscal 2017, the Company recorded $138 million of transaction and integration costs which generated a $31 million tax benefit. In the second quarter of fiscal 2017, the Company recorded pension mark-to-market gains of $18 million , which resulted in tax expense of $8 million . In the second quarter of fiscal 2017, the Company recorded $99 million of significant restructuring and impairment costs. Refer to Note 8, "Significant Restructuring and Impairment Costs," of the notes to consolidated financial statements for additional information. The restructuring costs generated a $20 million tax benefit, which reflects the Company’s current tax position in these jurisdictions. In the first quarter of fiscal 2017, the Company recorded a discrete tax benefit of $101 million due to changes in entity tax status. In the first quarter of fiscal 2017, the Company recorded pension mark-to-market gains of $117 million , which resulted in tax expense of $46 million . In the first quarter of fiscal 2017, the Company recorded $130 million of transaction and integration costs which generated an $11 million tax benefit. In the first quarter of fiscal 2017, the Company recorded $78 million of significant restructuring and impairment costs. Refer to Note 8, "Significant Restructuring and Impairment Costs," of the notes to consolidated financial statements for additional information. The restructuring costs generated a $14 million tax benefit, which reflects the Company’s current tax position in these jurisdictions.

Pension and Postretirement Plan

Pension and Postretirement Plans	9 Months Ended
	Jun. 30, 2018
Defined Benefit Plan [Abstract]
Pension and Postretirement Plans	Pension and Postretirement Plans The components of the Company’s net periodic benefit costs from continuing operations associated with its defined benefit pension and postretirement plans are shown in the tables below in accordance with ASC 715, "Compensation – Retirement Benefits" (in millions): U.S. Pension Plans Three Months Ended June 30, Nine Months Ended June 30, 2018 2017 2018 2017 Service cost $ 4 $ 4 $ 11 $ 13 Interest cost 27 28 80 85 Expected return on plan assets (58 ) (57 ) (172 ) (174 ) Net actuarial (gain) loss — 45 — (90 ) Settlement (gain) loss — 1 — (8 ) Net periodic benefit cost (credit) $ (27 ) $ 21 $ (81 ) $ (174 ) Non-U.S. Pension Plans Three Months Ended June 30, Nine Months Ended June 30, 2018 2017 2018 2017 Service cost $ 6 $ 8 $ 18 $ 24 Interest cost 14 13 43 36 Expected return on plan assets (29 ) (23 ) (87 ) (68 ) Net periodic benefit credit $ (9 ) $ (2 ) $ (26 ) $ (8 ) Postretirement Benefits Three Months Ended June 30, Nine Months Ended June 30, 2018 2017 2018 2017 Service cost $ — $ — $ 1 $ 1 Interest cost 2 1 5 4 Expected return on plan assets (2 ) (2 ) (7 ) (7 ) Net periodic benefit credit $ — $ (1 ) $ (1 ) $ (2 ) During the three and nine months ended June 30, 2017, the amount of lump sum payouts triggered a remeasurement event for certain U.S. pension plans resulting in the recognition of net actuarial (gains) losses of $45 million and $(90) million , respectively.

Debt and Financing Arrangements

Debt and Financing Arrangements	9 Months Ended
	Jun. 30, 2018
Debt Disclosure [Abstract]
Debt and Financing Arrangements	Debt and Financing Arrangements In October 2017, the Company completed the previously announced sale of its Scott Safety business to 3M. Net cash proceeds from the transaction of approximately $1.9 billion were used to repay a significant portion of the TSarl $4.0 billion of merger-related debt. In addition, in March 2018, the Company repaid $26 million in principal amount, plus accrued interest and in April 2018, the Company refinanced approximately $400 million in principal amount, plus accrued interest of the TSarl merger-related debt with commercial paper. In March 2018, the Company increased the committed credit limit from $1.0 billion to $1.25 billion on TSarl's committed revolving credit facility scheduled to expire in August 2020. As of June 30, 2018 , there were no draws on the facility. In March 2018, the Company entered into a 364 -day $250 million committed revolving credit facility scheduled to expire in March 2019. As of June 30, 2018, there were no draws on the facility. In March 2018, a 364 -day $150 million committed revolving credit facility expired. The Company entered into a new $150 million committed revolving credit facility scheduled to expire in February 2019. As of June 30, 2018, there were no draws on the facility. In February 2018, a 364 -day $150 million committed revolving credit facility expired. The Company entered into a new $150 million committed revolving credit facility scheduled to expire in February 2019. As of June 30, 2018, there were no draws on the facility. In January 2018, a 364 -day $250 million committed revolving credit facility expired. The Company entered into a new $200 million committed revolving credit facility scheduled to expire in January 2019. As of June 30, 2018, there were no draws on the facility. In January 2018, the Company retired $67 million in principal amount, plus accrued interest, of its 3.75% fixed rate notes that expired in January 2018. In December 2017, the Company repaid a 364 -day 150 million euro floating rate term loan, plus accrued interest, scheduled to mature in September 2018. In November 2017, the Company issued 750 million euro in principal amount of 0.0% senior unsecured fixed rate notes due in December 2020. Proceeds from the issuance were used to repay existing debt and for other general corporate purposes. In November 2017, the Company retired $300 million in principal amount, plus accrued interest, of its 1.4% fixed rate notes that expired in November 2017. Net Financing Charges The Company's net financing charges line item in the consolidated statements of income for the three and nine months ended June 30, 2018 and 2017 contained the following components (in millions): Three Months Ended June 30, Nine Months Ended June 30, 2018 2017 2018 2017 Interest expense, net of capitalized interest costs $ 110 $ 115 $ 328 $ 343 Banking fees and bond cost amortization 14 14 41 55 Interest income (10 ) (4 ) (24 ) (16 ) Net foreign exchange results for financing activities (13 ) (1 ) (13 ) (6 ) Net financing charges $ 101 $ 124 $ 332 $ 376 Net financing charges for the nine month period ended June 30, 2017 , included $17 million of transaction costs related primarily to the prior year debt exchange offer fees.

Stock-Based Compensation (Notes

Stock-Based Compensation (Notes)	9 Months Ended
	Jun. 30, 2018
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Stock-Based Compensation	Stock-Based Compensation During September 2016, the Board of Directors of the Company approved amendments to the Johnson Controls International plc 2012 Share and Incentive Plan (the "Plan"). The types of awards authorized by the Plan comprise of stock options, stock appreciation rights, performance shares, performance units and other stock-based compensation awards. The Compensation Committee of the Company's Board of Directors determines the types of awards to be granted to individual participants and the terms and conditions of the awards. Awards are typically granted annually in the Company’s fiscal first quarter. A summary of the stock-based awards granted during the nine month periods ended June 30, 2018 and 2017 is presented below: Nine Months Ended June 30, 2018 2017 Number Granted Weighted Average Grant Date Fair Value Number Granted Weighted Average Grant Date Fair Value Stock options 1,376,807 $ 7.04 2,841,686 $ 7.81 Stock appreciation rights — — 15,693 8.28 Restricted stock/units 2,188,131 37.26 1,671,677 41.75 Performance shares 496,478 36.31 846,725 48.40 Stock Options Stock options are granted with an exercise price equal to the market price of the Company’s stock at the date of grant. Stock option awards typically vest between two and three years after the grant date and expire ten years from the grant date. The fair value of each option is estimated on the date of grant using a Black-Scholes option valuation model that uses the assumptions noted in the following table. The expected life of options represents the period of time that options granted are expected to be outstanding, assessed separately for executives and non-executives. The risk-free interest rate for periods during the contractual life of the option is based on the U.S. Treasury yield curve in effect at the time of grant. For fiscal 2018, the expected volatility is based on the historical volatility of the Company’s stock after the Adient spin-off blended with the historical volatility of certain peer companies’ stock prior to the Adient spin-off over the most recent period corresponding to the expected life as of the grant date. For fiscal 2017, the expected volatility is based on the historical volatility of certain peer companies over the most recent period corresponding to the expected life as of the grant date. The expected dividend yield is based on the expected annual dividend as a percentage of the market value of the Company’s ordinary shares as of the grant date. The Company uses historical data to estimate option exercises and employee terminations within the valuation model. Nine Months Ended 2018 2017 Expected life of option (years) 6.5 4.75 & 6.5 Risk-free interest rate 2.28% 1.23% - 1.93% Expected volatility of the Company’s stock 23.7% 24.60% Expected dividend yield on the Company’s stock 2.78% 2.21% Stock Appreciation Rights ("SARs") SARs vest under the same terms and conditions as stock option awards; however, they are settled in cash for the difference between the market price on the date of exercise and the exercise price. As a result, SARs are recorded in the Company’s consolidated statements of financial position as a liability until the date of exercise. The fair value of each SAR award is estimated using a similar method described for stock options. The fair value of each SAR award is recalculated at the end of each reporting period and the liability and expense are adjusted based on the new fair value. Restricted (Nonvested) Stock / Units The Plan provides for the award of restricted stock or restricted stock units to certain employees. These awards are typically share settled unless the employee is a non-U.S. employee or elects to defer settlement until retirement at which point the award would be settled in cash. Restricted awards typically vest over a period of three years from the grant date. The Plan allows for different vesting terms on specific grants with approval by the Board of Directors. The fair value of each share-settled restricted award is based on the closing market value of the Company’s ordinary shares on the date of grant. The fair value of each cash-settled restricted award is recalculated at the end of each reporting period based on the closing market value of the Company's ordinary shares at the end of the reporting period, and the liability and expense are adjusted based on the new fair value. Performance Share Awards The Plan permits the grant of performance-based share unit ("PSU") awards. The PSUs are generally contingent on the achievement of pre-determined performance goals over a three -year performance period as well as on the award holder's continuous employment until the vesting date. The PSUs are also indexed to the achievement of specified levels of total shareholder return versus a peer group over the performance period. Each PSU that is earned will be settled with shares of the Company's ordinary shares following the completion of the performance period, unless the award holder elected to defer a portion or all of the award until retirement which would then be settled in cash. The fair value of each PSU is estimated on the date of grant using a Monte Carlo simulation that uses the assumptions noted in the following table. The risk-free interest rate for periods during the contractual life of the PSU is based on the U.S. Treasury yield curve in effect at the time of grant. For fiscal 2018, the expected volatility is based on the historical volatility of the Company’s stock after the Adient spin-off blended with the historical volatility of certain peer companies’ stock prior to the Adient spin-off over the most recent three-year period as of the grant date. For fiscal 2017, the expected volatility is based on historical volatility of certain peer companies over the most recent three-year period as of the grant date. Nine Months Ended 2018 2017 Risk-free interest rate 1.92% 1.40% Expected volatility of the Company’s stock 21.7% 21.0%

Earnings Per Share

Earnings Per Share	9 Months Ended
	Jun. 30, 2018
Earnings Per Share [Abstract]
Earnings Per Share	Earnings Per Share The Company presents both basic and diluted earnings per share ("EPS") amounts. Basic EPS is calculated by dividing net income attributable to Johnson Controls by the weighted average number of ordinary shares outstanding during the reporting period. Diluted EPS is calculated by dividing net income attributable to Johnson Controls by the weighted average number of ordinary shares and ordinary equivalent shares outstanding during the reporting period that are calculated using the treasury stock method for stock options, unvested restricted stock and unvested performance share awards. The treasury stock method assumes that the Company uses the proceeds from the exercise of stock option awards to repurchase ordinary shares at the average market price during the period. The assumed proceeds under the treasury stock method include the purchase price that the grantee will pay in the future and compensation cost for future service that the Company has not yet recognized. For unvested restricted stock and unvested performance share awards, assumed proceeds under the treasury stock method would include unamortized compensation cost. The following table reconciles the numerators and denominators used to calculate basic and diluted earnings per share (in millions): Three Months Ended June 30, Nine Months Ended June 30, 2018 2017 2018 2017 Income Available to Ordinary Shareholders Income from continuing operations $ 723 $ 555 $ 1,391 $ 779 Loss from discontinued operations — — — (43 ) Basic and diluted income available to shareholders $ 723 $ 555 $ 1,391 $ 736 Weighted Average Shares Outstanding Basic weighted average shares outstanding 925.6 935.4 926.0 937.2 Effect of dilutive securities: Stock options, unvested restricted stock and unvested performance share awards 5.1 9.0 6.1 9.6 Diluted weighted average shares outstanding 930.7 944.4 932.1 946.8 Antidilutive Securities Options to purchase shares 2.1 0.1 1.5 0.1 During the three months ended June 30, 2018 and 2017 , the Company declared a dividend of $0.26 and $0.25 , respectively, per share. During the nine months ended June 30, 2018 and 2017 , the Company declared dividends of $0.78 and $0.75 , respectively, per share. The Company paid all dividends in the month subsequent to the end of each fiscal quarter.

Equity and Noncontrolling Inter

Equity and Noncontrolling Interests	9 Months Ended
	Jun. 30, 2018
Stockholders' Equity Note [Abstract]
Equity and Noncontrolling Interests	Equity and Noncontrolling Interests Other comprehensive income includes activity relating to discontinued operations. The following schedules present changes in consolidated equity attributable to Johnson Controls and noncontrolling interests (in millions, net of tax): Three Months Ended June 30, 2018 Three Months Ended June 30, 2017 Equity Attributable to Johnson Controls International plc Equity Attributable to Noncontrolling Interests Total Equity Equity Attributable to Johnson Controls International plc Equity Attributable to Noncontrolling Interests Total Equity Beginning balance, March 31 $ 20,874 $ 1,006 $ 21,880 $ 19,388 $ 813 $ 20,201 Total comprehensive income: Net income 723 71 794 555 66 621 Foreign currency translation adjustments (557 ) (44 ) (601 ) 268 3 271 Realized and unrealized gains (losses) on derivatives 3 (1 ) 2 (7 ) (1 ) (8 ) Realized and unrealized losses on marketable securities — — — (3 ) — (3 ) Other comprehensive income (loss) (554 ) (45 ) (599 ) 258 2 260 Comprehensive income 169 26 195 813 68 881 Other changes in equity: Cash dividends—ordinary shares (240 ) — (240 ) (234 ) — (234 ) Repurchases of ordinary shares (56 ) — (56 ) (307 ) — (307 ) Change in noncontrolling interest share — 4 4 — 3 3 Other, including options exercised 26 — 26 71 — 71 Ending balance, June 30 $ 20,773 $ 1,036 $ 21,809 $ 19,731 $ 884 $ 20,615 Nine Months Ended June 30, 2018 Nine Months Ended June 30, 2017 Equity Attributable to Johnson Controls International plc Equity Attributable to Noncontrolling Interests Total Equity Equity Attributable to Johnson Controls International plc Equity Attributable to Noncontrolling Interests Total Equity Beginning balance, September 30, $ 20,447 $ 920 $ 21,367 $ 24,118 $ 972 $ 25,090 Total comprehensive income: Net income 1,391 132 1,523 736 127 863 Foreign currency translation adjustments (331 ) 3 (328 ) (150 ) (22 ) (172 ) Realized and unrealized gains (losses) on derivatives (2 ) 1 (1 ) (13 ) 1 (12 ) Realized and unrealized gains (losses) on marketable securities (2 ) — (2 ) 6 — 6 Other comprehensive income (loss) (335 ) 4 (331 ) (157 ) (21 ) (178 ) Comprehensive income 1,056 136 1,192 579 106 685 Other changes in equity: Cash dividends—ordinary shares (722 ) — (722 ) (705 ) — (705 ) Dividends attributable to noncontrolling interests — (43 ) (43 ) — (47 ) (47 ) Repurchases of ordinary shares (255 ) — (255 ) (426 ) — (426 ) Change in noncontrolling interest share — 23 23 — (9 ) (9 ) Adoption of ASU 2016-09 179 — 179 — — — Spin-off of Adient — — — (4,038 ) (138 ) (4,176 ) Other, including options exercised 68 — 68 203 — 203 Ending balance, June 30 $ 20,773 $ 1,036 $ 21,809 $ 19,731 $ 884 $ 20,615 As previously disclosed, during the quarter ended December 31, 2017, the Company adopted ASU No. 2016-09. As a result, the Company recognized deferred tax assets of $179 million related to certain operating loss carryforwards resulting from the exercise of employee stock options and restricted stock vestings on a modified retrospective basis through a cumulative-effect adjustment to retained earnings as of October 1, 2017. As previously disclosed, on October 31, 2016, the Company completed the Adient spin-off. As a result of the spin-off, the Company divested net assets of approximately $4.0 billion . Following the Tyco Merger, the Company adopted, subject to the ongoing existence of sufficient distributable reserves, the existing Tyco International plc $1 billion share repurchase program in September 2016. In December 2017, the Company's Board of Directors approved an $1 billion increase to its share repurchase authorization. The share repurchase program does not have an expiration date and may be amended or terminated by the Board of Directors at any time without prior notice. For the three and nine month periods ended June 30, 2018 , the Company repurchased $56 million and $255 million of its ordinary shares, respectively. For the three and nine month periods ended June 30, 2017 , the Company repurchased $307 million and $426 million of its ordinary shares, respectively. As of June 30, 2018 , approximately $1.1 billion remains available under the share repurchase program. The Company consolidates certain subsidiaries in which the noncontrolling interest party has within its control the right to require the Company to redeem all or a portion of its interest in the subsidiary. The redeemable noncontrolling interests are reported at their estimated redemption value. Any adjustment to the redemption value impacts retained earnings but does not impact net income. Redeemable noncontrolling interests which are redeemable only upon future events, the occurrence of which is not currently probable, are recorded at carrying value. The following schedules present changes in the redeemable noncontrolling interests (in millions): Three Months Ended June 30, 2018 2017 Beginning balance, March 31 $ 235 $ 168 Net income 10 8 Foreign currency translation adjustments (13 ) 14 Realized and unrealized losses on derivatives (1 ) (1 ) Ending balance, June 30 $ 231 $ 189 Nine Months Ended June 30, 2018 2017 Beginning balance, September 30 $ 211 $ 234 Net income 35 29 Foreign currency translation adjustments (3 ) 6 Realized and unrealized losses on derivatives (9 ) (1 ) Dividends (3 ) (43 ) Spin-off of Adient — (36 ) Ending balance, June 30 $ 231 $ 189 The following schedules present changes in accumulated other comprehensive income ("AOCI") attributable to Johnson Controls (in millions, net of tax): Three Months Ended June 30, 2018 2017 Foreign currency translation adjustments ("CTA") Balance at beginning of period $ (255 ) $ (1,007 ) Aggregate adjustment for the period (net of tax effect of $0 and $(5)) (557 ) 268 Balance at end of period (812 ) (739 ) Realized and unrealized gains (losses) on derivatives Balance at beginning of period 1 14 Current period changes in fair value (net of tax effect of $1 and $(1)) 5 (1 ) Reclassification to income (net of tax effect of $(2) and $(5)) ** (2 ) (6 ) Balance at end of period 4 7 Realized and unrealized gains (losses) on marketable securities Balance at beginning of period 2 8 Current period changes in fair value (net of tax effect of $0 and $1) 1 (3 ) Reclassification to income (net of tax effect of $(1) and $0) *** (1 ) — Balance at end of period 2 5 Pension and postretirement plans Balance at beginning of period (2 ) (2 ) Other changes — — Balance at end of period (2 ) (2 ) Accumulated other comprehensive loss, end of period $ (808 ) $ (729 ) Nine Months Ended June 30, 2018 2017 CTA Balance at beginning of period $ (481 ) $ (1,152 ) Aggregate adjustment for the period (net of tax effect of $1 and $0) * (331 ) (150 ) Adient spin-off impact (net of tax effect of $0) — 563 Balance at end of period (812 ) (739 ) Realized and unrealized gains (losses) on derivatives Balance at beginning of period 6 4 Current period changes in fair value (net of tax effect of $2 and $3) 7 6 Reclassification to income (net of tax effect of $(4) and $(12)) ** (9 ) (19 ) Adient spin-off impact (net of tax effect of $0 and $6) — 16 Balance at end of period 4 7 Realized and unrealized gains (losses) on marketable securities Balance at beginning of period 4 (1 ) Current period changes in fair value (net of tax effect of $0 and $1) (1 ) 6 Reclassification to income (net of tax effect of $(1) and $0) *** (1 ) — Balance at end of period 2 5 Pension and postretirement plans Balance at beginning of period (2 ) (4 ) Adient spin-off impact (net of tax effect of $0) — 2 Balance at end of period (2 ) (2 ) Accumulated other comprehensive loss, end of period $ (808 ) $ (729 ) * During the nine months ended June 30, 2018, $12 million of cumulative CTA was recognized as part of the divestiture-related gain recognized as part of the divestiture of Scott Safety. ** Refer to Note 15, "Derivative Instruments and Hedging Activities," of the notes to consolidated financial statements for disclosure of the line items in the consolidated statements of income affected by reclassifications from AOCI into income related to derivatives. ***During the nine months ended June 30, 2018, the Company sold certain marketable common stock for approximately $3 million . As a result, the Company recorded $2 million of realized gains within selling, general and administrative expenses.

Derivative Instruments and Hedg

Derivative Instruments and Hedging Activities	9 Months Ended
	Jun. 30, 2018
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Instruments and Hedging Activities	Derivative Instruments and Hedging Activities The Company selectively uses derivative instruments to reduce market risk associated with changes in foreign currency, commodities, stock-based compensation liabilities and interest rates. Under Company policy, the use of derivatives is restricted to those intended for hedging purposes; the use of any derivative instrument for speculative purposes is strictly prohibited. A description of each type of derivative utilized by the Company to manage risk is included in the following paragraphs. In addition, refer to Note 16, "Fair Value Measurements," of the notes to consolidated financial statements for information related to the fair value measurements and valuation methods utilized by the Company for each derivative type. Cash Flow Hedges The Company has global operations and participates in the foreign exchange markets to minimize its risk of loss from fluctuations in foreign currency exchange rates. The Company selectively hedges anticipated transactions that are subject to foreign exchange rate risk primarily using foreign currency exchange hedge contracts. The Company hedges 70% to 90% of the nominal amount of each of its known foreign exchange transactional exposures. As cash flow hedges under ASC 815, "Derivatives and Hedging," the hedge gains or losses due to changes in fair value are initially recorded as a component of AOCI and are subsequently reclassified into earnings when the hedged transactions occur and affect earnings. These contracts were highly effective in hedging the variability in future cash flows attributable to changes in currency exchange rates during the three and nine months ended June 30, 2018 and 2017 . The Company selectively hedges anticipated transactions that are subject to commodity price risk, primarily using commodity hedge contracts, to minimize overall price risk associated with the Company’s purchases of lead, copper, tin, aluminum and polypropylene in cases where commodity price risk cannot be naturally offset or hedged through supply base fixed price contracts. Commodity risks are systematically managed pursuant to policy guidelines. As cash flow hedges, the hedge gains or losses due to changes in fair value are initially recorded as a component of AOCI and are subsequently reclassified into earnings when the hedged transactions, typically sales, occur and affect earnings. The maturities of the commodity hedge contracts coincide with the expected purchase of the commodities. These contracts were highly effective in hedging the variability in future cash flows attributable to changes in commodity prices during the three and nine months ended June 30, 2018 and 2017 . The Company had the following outstanding contracts to hedge forecasted commodity purchases (in metric tons): Volume Outstanding as of Commodity June 30, 2018 September 30, 2017 Copper 2,948 1,962 Polypropylene 8,540 19,563 Lead 31,009 24,705 Aluminum 3,885 2,169 Tin 2,276 1,715 Fair Value Hedges The Company selectively uses interest rate swaps to reduce market risk associated with changes in interest rates for its fixed-rate bonds. As fair value hedges, the interest rate swaps and related debt balances are valued under a market approach using publicized swap curves. Changes in the fair value of the swap and hedged portion of the debt are recorded in the consolidated statements of income. As of September 30, 2016, the Company had four fixed to floating interest rate swaps totaling $400 million to hedge the coupon of its 2.6% notes that matured in December 2016, three fixed to floating interest rate swaps totaling $300 million to hedge the coupon of its 1.4% notes maturing November 2017 and one fixed to floating interest rate swap totaling $150 million to hedge the coupon of its 7.125% notes maturing July 2017. In December 2016, the four remaining outstanding interest rate swaps were terminated. The Company had no interest rate swaps outstanding at June 30, 2018 and September 30, 2017 , respectively. Net Investment Hedges The Company enters into foreign currency denominated debt obligations to selectively hedge portions of its net investment in non-U.S. subsidiaries. The currency effects of the debt obligations are reflected in the AOCI account within shareholders’ equity attributable to Johnson Controls ordinary shareholders where they offset currency gains and losses recorded on the Company’s net investments globally. At June 30, 2018 , the Company had one billion euro, 750 million euro, 423 million euro and 58 million euro bonds designated as net investment hedges in the Company's net investment in Europe and 35 billion yen of foreign denominated debt designated as net investment hedge in the Company's net investment in Japan. At September 30, 2017 , the Company had one billion euro, 423 million euro and 58 million euro bonds designated as net investment hedges in the Company's net investment in Europe and 35 billion yen of foreign denominated debt designated as net investment hedge in the Company's net investment in Japan. Derivatives Not Designated as Hedging Instruments The Company selectively uses equity swaps to reduce market risk associated with certain of its stock-based compensation plans, such as its deferred compensation plans. These equity compensation liabilities increase as the Company’s stock price increases and decrease as the Company’s stock price decreases. In contrast, the value of the swap agreement moves in the opposite direction of these liabilities, allowing the Company to fix a portion of the liabilities at a stated amount. As of June 30, 2018 , the Company hedged approximately 1.8 million shares of its ordinary shares, which have a cost basis of $73 million . As of September 30, 2017 , the Company hedged approximately 1.4 million shares of its ordinary shares, which have a cost basis of $58 million . The Company also holds certain foreign currency forward contracts which do not qualify for hedge accounting treatment. The change in fair value of foreign currency exchange derivatives not designated as hedging instruments under ASC 815 are recorded in the consolidated statements of income. Fair Value of Derivative Instruments The following table presents the location and fair values of derivative instruments and hedging activities included in the Company’s consolidated statements of financial position (in millions): Derivatives and Hedging Activities Designated as Hedging Instruments under ASC 815 Derivatives and Hedging Activities Not Designated as Hedging Instruments under ASC 815 June 30, September 30, June 30, September 30, 2018 2017 2018 2017 Other current assets Foreign currency exchange derivatives $ 8 $ 27 $ 11 $ — Commodity derivatives 2 9 — — Other noncurrent assets Equity swap — — 60 55 Total assets $ 10 $ 36 $ 71 $ 55 Other current liabilities Foreign currency exchange derivatives $ 7 $ 21 $ 22 $ 25 Commodity derivatives 3 1 — — Long-term debt Foreign currency denominated debt 2,916 2,058 — — Total liabilities $ 2,926 $ 2,080 $ 22 $ 25 Counterparty Credit Risk The use of derivative financial instruments exposes the Company to counterparty credit risk. The Company has established policies and procedures to limit the potential for counterparty credit risk, including establishing limits for credit exposure and continually assessing the creditworthiness of counterparties. As a matter of practice, the Company deals with major banks worldwide having strong investment grade long-term credit ratings. To further reduce the risk of loss, the Company generally enters into International Swaps and Derivatives Association ("ISDA") master netting agreements with substantially all of its counterparties. The Company's derivative contracts do not contain any credit risk related contingent features and do not require collateral or other security to be furnished by the Company or the counterparties. The Company's exposure to credit risk associated with its derivative instruments is measured on an individual counterparty basis, as well as by groups of counterparties that share similar attributes. The Company does not anticipate any non-performance by any of its counterparties, and the concentration of risk with financial institutions does not present significant credit risk to the Company. The Company enters into ISDA master netting agreements with counterparties that permit the net settlement of amounts owed under the derivative contracts. The master netting agreements generally provide for net settlement of all outstanding contracts with a counterparty in the case of an event of default or a termination event. The Company has not elected to offset the fair value positions of the derivative contracts recorded in the consolidated statements of financial position. Collateral is generally not required of the Company or the counterparties under the master netting agreements. As of June 30, 2018 and September 30, 2017 , no cash collateral was received or pledged under the master netting agreements. The gross and net amounts of derivative assets and liabilities were as follows (in millions): Fair Value of Assets Fair Value of Liabilities June 30, September 30, June 30, September 30, 2018 2017 2018 2017 Gross amount recognized $ 81 $ 91 $ 2,948 $ 2,105 Gross amount eligible for offsetting (18 ) (16 ) (18 ) (16 ) Net amount $ 63 $ 75 $ 2,930 $ 2,089 Derivatives Impact on the Statements of Income and Statements of Comprehensive Income The following table presents the pre-tax gains (losses) recorded in other comprehensive income (loss) related to cash flow hedges for the three and nine months ended June 30, 2018 and 2017 (in millions): Derivatives in ASC 815 Cash Flow Hedging Relationships Three Months Ended June 30, Nine Months Ended June 30, 2018 2017 2018 2017 Foreign currency exchange derivatives $ 6 $ (3 ) $ 7 $ 3 Commodity derivatives — 1 2 6 Total $ 6 $ (2 ) $ 9 $ 9 The following tables present the location and amount of the pre-tax gains (losses) on cash flow hedges reclassified from AOCI into the Company’s consolidated statements of income for the three and nine months ended June 30, 2018 and 2017 (in millions): Derivatives in ASC 815 Cash Flow Hedging Relationships Location of Gain (Loss) Reclassified from AOCI into Income Three Months Ended June 30, Nine Months Ended June 30, 2018 2017 2018 2017 Foreign currency exchange derivatives Cost of sales $ 2 $ 8 $ 2 $ 24 Commodity derivatives Cost of sales 2 3 11 7 Total $ 4 $ 11 $ 13 $ 31 The following table presents the location and amount of pre-tax gains (losses) on fair value hedges recognized in the Company’s consolidated statements of income for the three and nine months ended June 30, 2018 and 2017 (in millions): Derivatives in ASC 815 Fair Value Hedging Relationships Location of Gain (Loss) Recognized in Income on Derivative Three Months Ended June 30, Nine Months Ended June 30, 2018 2017 2018 2017 Interest rate swap Net financing charges $ — $ — $ — $ (1 ) Fixed rate debt swapped to floating Net financing charges — — — 2 Total $ — $ — $ — $ 1 The following table presents the location and amount of pre-tax gains (losses) on derivatives not designated as hedging instruments recognized in the Company’s consolidated statements of income for the three and nine months ended June 30, 2018 and 2017 (in millions): Amount of Gain (Loss) Recognized in Income on Derivative Derivatives Not Designated as Hedging Instruments under ASC 815 Location of Gain (Loss) Recognized in Income on Derivative Three Months Ended June 30, Nine Months Ended June 30, 2018 2017 2018 2017 Foreign currency exchange derivatives Cost of sales $ (4 ) $ (4 ) $ (6 ) $ (1 ) Foreign currency exchange derivatives Net financing charges (27 ) 51 (26 ) 60 Foreign currency exchange derivatives Income tax provision — 1 2 (2 ) Foreign currency exchange derivatives Income (loss) from discontinued operations — — — 5 Equity swap Selling, general and administrative (3 ) 2 (10 ) 2 Total $ (34 ) $ 50 $ (40 ) $ 64 The pre-tax gains (losses) recorded in CTA within other comprehensive income (loss) related to net investment hedges were $165 million and $(105) million for the three months ended June 30, 2018 and 2017 , respectively. The pre-tax gains (losses) recorded in CTA within other comprehensive income (loss) related to net investment hedges were $29 million and $(77) million for the nine months ended June 30, 2018 and 2017 , respectively. For the three and nine months ended June 30, 2018 and 2017 , no gains or losses were reclassified from CTA into income for the Company’s outstanding net investment hedges.

Fair Value Measurements

Fair Value Measurements	9 Months Ended
	Jun. 30, 2018
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value Measurements ASC 820, "Fair Value Measurement," defines fair value as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. ASC 820 also establishes a three-level fair value hierarchy that prioritizes information used in developing assumptions when pricing an asset or liability as follows: Level 1: Observable inputs such as quoted prices in active markets for identical assets or liabilities; Level 2: Quoted prices in active markets for similar assets or liabilities, quoted prices for identical or similar assets or liabilities in markets that are not active, or inputs, other than quoted prices in active markets, that are observable either directly or indirectly; and Level 3: Unobservable inputs where there is little or no market data, which requires the reporting entity to develop its own assumptions. ASC 820 requires the use of observable market data, when available, in making fair value measurements. When inputs used to measure fair value fall within different levels of the hierarchy, the level within which the fair value measurement is categorized is based on the lowest level input that is significant to the fair value measurement. Recurring Fair Value Measurements The following tables present the Company’s fair value hierarchy for those assets and liabilities measured at fair value as of June 30, 2018 and September 30, 2017 (in millions): Fair Value Measurements Using: Total as of June 30, 2018 Quoted Prices in Active Markets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Other current assets Foreign currency exchange derivatives $ 19 $ — $ 19 $ — Commodity derivatives 2 — 2 — Exchange traded funds (fixed income) 1 14 14 — — Other noncurrent assets Investments in marketable common stock 4 4 — — Deferred compensation plan assets 97 97 — — Exchange traded funds (fixed income) 1 148 148 — — Exchange traded funds (equity) 1 112 112 — — Equity swap 60 60 — Total assets $ 456 $ 375 $ 81 $ — Other current liabilities Foreign currency exchange derivatives $ 29 $ — $ 29 $ — Commodity derivatives 3 — 3 — Total liabilities $ 32 $ — $ 32 $ — Fair Value Measurements Using: Total as of September 30, 2017 Quoted Prices in Active Markets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Other current assets Foreign currency exchange derivatives $ 27 $ — $ 27 $ — Commodity derivatives 9 — 9 — Exchange traded funds (fixed income) 1 14 14 — — Other noncurrent assets Investments in marketable common stock 10 10 — — Deferred compensation plan assets 92 92 — — Exchange traded funds (fixed income) 1 155 155 — — Exchange traded funds (equity) 1 100 100 — — Equity swap 55 — 55 — Total assets $ 462 $ 371 $ 91 $ — Other current liabilities Foreign currency exchange derivatives $ 46 $ — $ 46 $ — Commodity derivatives 1 — 1 — Total liabilities $ 47 $ — $ 47 $ — 1 Classified as restricted investments for payment of asbestos liabilities. See Note 20, "Commitments and Contingencies," of the notes to consolidated financial statements for further details. Valuation Methods Foreign currency exchange derivatives : The foreign currency exchange derivatives are valued under a market approach using publicized spot and forward prices. Commodity derivatives : The commodity derivatives are valued under a market approach using publicized prices, where available, or dealer quotes. Equity swaps : The equity swaps are valued under a market approach as the fair value of the swaps is equal to the Company’s stock price at the reporting period date. Deferred compensation plan assets : Assets held in the deferred compensation plans will be used to pay benefits under certain of the Company's non-qualified deferred compensation plans. The investments primarily consist of mutual funds which are publicly traded on stock exchanges and are valued using a market approach based on the quoted market prices. Investments in marketable common stock and exchange traded funds : Investments in marketable common stock and exchange traded funds are valued using a market approach based on the quoted market prices, where available, or broker/dealer quotes of identical or comparable instruments. The Company recorded unrealized gains of $20 million and unrealized losses of $18 million on these investments as of June 30, 2018 within AOCI in the consolidated statements of financial position. The Company recorded unrealized gains of $10 million and unrealized losses of $6 million on these investments as of September 30, 2017 within AOCI in the consolidated statements of financial position. During the nine months ended June 30, 2018, the Company sold certain marketable common stock for approximately $3 million . As a result, the Company recorded $2 million of realized gains within selling, general and administrative expenses. The fair values of cash and cash equivalents, accounts receivable, short-term debt and accounts payable approximate their carrying values. The fair value of long-term debt was $10.4 billion and $12.7 billion at June 30, 2018 and September 30, 2017 , respectively. The fair value of public debt was $8.7 billion and $8.6 billion , at June 30, 2018 and September 30, 2017 , respectively, which was determined primarily using market quotes classified as Level 1 inputs within the ASC 820 fair value hierarchy. The fair value of other long-term debt was $1.7 billion and $4.1 billion at June 30, 2018 and September 30, 2017 , respectively, which was determined based on quoted market prices for similar instruments classified as Level 2 inputs within the ASC 820 fair value hierarchy.

Impairment of Long-Lived Assets

Impairment of Long-Lived Assets (Notes)	9 Months Ended
	Jun. 30, 2018
Disclosure of Impairment of Long-Lived Assets [Abstract]
Impairment of Long-Lived Assets	Impairment of Long-Lived Assets The Company reviews long-lived assets, including tangible assets and other intangible assets with definitive lives, for impairment whenever events or changes in circumstances indicate that the asset’s carrying amount may not be recoverable. The Company conducts its long-lived asset impairment analyses in accordance with ASC 360-10-15, "Impairment or Disposal of Long-Lived Assets," ASC 350-30, "General Intangibles Other than Goodwill" and ASC 985-20, "Costs of software to be sold, leased, or marketed." ASC 360-10-15 requires the Company to group assets and liabilities at the lowest level for which identifiable cash flows are largely independent of the cash flows of other assets and liabilities and evaluate the asset group against the sum of the undiscounted future cash flows. If the undiscounted cash flows do not indicate the carrying amount of the asset group is recoverable, an impairment charge is measured as the amount by which the carrying amount of the asset group exceeds its fair value based on discounted cash flow analysis or appraisals. ASC 350-30 requires intangible assets acquired in a business combination that are used in research and development activities to be considered indefinite lived until the completion or abandonment of the associated research and development efforts. During the period that those assets are considered indefinite lived, they shall not be amortized but shall be tested for impairment annually and more frequently if events or changes in circumstances indicate that it is more likely than not that the asset is impaired. If the carrying amount of an intangible asset exceeds its fair value, an entity shall recognize an impairment loss in an amount equal to that excess. ASC 985-20 requires the unamortized capitalized costs of a computer software product be compared to the net realizable value of that product. The amount by which the unamortized capitalized costs of a computer software product exceed the net realizable value of that asset shall be written off. In the first quarter of fiscal 2018, the Company concluded it had a triggering event requiring assessment of impairment for certain of its long-lived assets in conjunction with its restructuring actions announced in fiscal 2018. As a result, the Company reviewed the long-lived assets for impairment and recorded $30 million of asset impairment charges within restructuring and impairment costs in the consolidated statements of income. Of the total impairment charges, $23 million related to the Global Products segment, $5 million related to Corporate assets and $2 million related to the Power Solutions segment. Refer to Note 8, "Significant Restructuring and Impairment Costs," of the notes to consolidated financial statements for additional information. The impairments were measured under a market approach utilizing an appraisal to determine fair values of the impaired assets. This method is consistent with the methods the Company employed in prior periods to value other long-lived assets. The inputs utilized in the analyses are classified as Level 3 inputs within the fair value hierarchy as defined in ASC 820, "Fair Value Measurement." In the first, second and third quarters of fiscal 2017, the Company concluded it had triggering events requiring assessment of impairment for certain of its long-lived assets in conjunction with its restructuring actions announced in fiscal 2017. As a result, the Company reviewed the long-lived assets for impairment and recorded $69 million of asset impairment charges within restructuring and impairment costs in the consolidated statements of income, of which $15 million was recorded in the first quarter, $23 million was recorded in the second quarter and $31 million was recorded in the third quarter. Of the total impairment charges, $28 million related to the Buildings North America segment, $20 million related to the Global Products segment, $17 million related to Corporate assets and $4 million related to the Power Solutions segment. Refer to Note 8, "Significant Restructuring and Impairment Costs," of the notes to consolidated financial statements for additional information. The impairments were measured, depending on the asset, under either an income approach utilizing forecasted discounted cash flows or a market approach utilizing an appraisal to determine fair values of the impaired assets. This method is consistent with the methods the Company employed in prior periods to value other long-lived assets. The inputs utilized in the analyses are classified as Level 3 inputs within the fair value hierarchy as defined in ASC 820, "Fair Value Measurement." At June 30, 2018 and 2017 , the Company concluded it did not have any other triggering events requiring assessment of impairment of its long-lived assets.

Segment Information

Segment Information	9 Months Ended
	Jun. 30, 2018
Segment Reporting, Disclosure of Entity's Reportable Segments [Abstract]
Segment Information	Segment Information five reportable segments for financial reporting purposes. The Company’s five reportable segments are presented in the context of its two primary businesses – Building Technologies & Solutions and Power Solutions. Effective July 1, 2017, the Company reorganized the reportable segments within its Building Technologies & Solutions business to align with its new management reporting structure and business activities. Prior to this reorganization, Building Technologies & Solutions was comprised of five reportable segments for financial reporting purposes: Systems and Service North America, Products North America, Asia, Rest of World and Tyco. As a result of this change, Building Technologies & Solutions is now comprised of four reportable segments for financial reporting purposes: Building Solutions North America, Building Solutions EMEA/LA, Building Solutions Asia Pacific and Global Products. Historical information has been revised to reflect the new Building Technologies & Solutions segments. A summary of the significant Building Technologies & Solutions reportable segment changes is as follows: • The “Systems and Service North America” segment is now part of the new “Building Solutions North America” reportable segment. • The North America Unitary Products business, Air Distribution Technologies business and refrigeration systems business, as well as HVAC products installed for Marine customers, previously included in the “Products North America” segment, are now part of the new reportable segment “Global Products.” The systems and products installation business for U.S. Navy customers, previously included in the “Products North America” segment, is now part of the new “Building Solutions North America” reportable segment. • The systems and service business within the former “Asia” segment is now part of the new “Building Solutions Asia Pacific” reportable segment. The HVAC products manufacturing business and the Johnson Controls-Hitachi joint venture, previously part of the “Asia” segment, are now part of the new “Global Products” reportable segment. • The systems and service businesses in Europe, the Middle East and Latin America within the former “Rest of World” segment are now part of the new “Building Solutions EMEA/LA” reportable segment. The HVAC products manufacturing businesses, previously part of the “Rest of World” segment, are now part of the new “Global Products” reportable segment. • As the Company has integrated the legacy Tyco business with its legacy Building Efficiency business for segment reporting purposes, Tyco is no longer a separate reportable segment. The Tyco businesses are now included throughout the new reportable segments. Building Technologies & Solutions • Building Solutions North America designs, sells, installs, and services HVAC and controls systems, integrated electronic security systems (including monitoring), and integrated fire detection and suppression systems for commercial, industrial, retail, small business, institutional and governmental customers in North America. Building Solutions North America also provides energy efficiency solutions and technical services, including inspection, scheduled maintenance, and repair and replacement of mechanical and control systems, to non-residential building and industrial applications in the North American marketplace. • Building Solutions EMEA/LA designs, sells, installs, and services HVAC, controls, refrigeration, integrated electronic security, integrated fire detection and suppression systems, and provides technical services to markets in Europe, the Middle East, Africa and Latin America. • Building Solutions Asia Pacific designs, sells, installs, and services HVAC, controls, refrigeration, integrated electronic security, integrated fire detection and suppression systems, and provides technical services to the Asia Pacific marketplace. • Global Products designs and produces heating and air conditioning for residential and commercial applications, and markets products and refrigeration systems to replacement and new construction market customers globally. The Global Products business also designs, manufactures and sells fire protection and security products, including intrusion security, anti-theft devices, and access control and video management systems, for commercial, industrial, retail, residential, small business, institutional and governmental customers worldwide. Global Products also includes the Johnson Controls-Hitachi joint venture, which was formed October 1, 2015, and included the Scott Safety business, prior to its sale on October 4, 2017. Power Solutions Power Solutions services both automotive original equipment manufacturers and the battery aftermarket by providing advanced battery technology, coupled with systems engineering, marketing and service expertise. Management evaluates the performance of its business segments primarily on segment earnings before interest, taxes and amortization ("EBITA"), which represents income 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 the net mark-to-market adjustments related to pension and postretirement plans. Financial information relating to the Company’s reportable segments is as follows (in millions): Net Sales Three Months Ended Nine Months Ended 2018 2017 2018 2017 Building Technologies & Solutions Building Solutions North America $ 2,246 $ 2,142 $ 6,355 $ 6,181 Building Solutions EMEA/LA 926 896 2,748 2,669 Building Solutions Asia Pacific 681 630 1,864 1,767 Global Products 2,429 2,406 6,250 6,214 6,282 6,074 17,217 16,831 Power Solutions 1,838 1,609 5,813 5,205 Total net sales $ 8,120 $ 7,683 $ 23,030 $ 22,036 Segment EBITA Three Months Ended Nine Months Ended 2018 2017 2018 2017 Building Technologies & Solutions Building Solutions North America $ 314 $ 290 $ 780 $ 741 Building Solutions EMEA/LA 96 100 242 238 Building Solutions Asia Pacific 97 85 242 215 Global Products 435 437 949 806 942 912 2,213 2,000 Power Solutions 310 304 1,008 996 Total 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 — (49 ) (158 ) (226 ) Net mark-to-market adjustments on pension plans — (45 ) — 90 Net financing charges (101 ) (124 ) (332 ) (376 ) Income from continuing operations before income taxes $ 910 $ 718 $ 2,009 $ 1,496

Guarantees

Guarantees	9 Months Ended
	Jun. 30, 2018
Guarantees [Abstract]
Guarantees	Guarantees Certain of the Company's subsidiaries at the business segment level have guaranteed the performance of third-parties and provided financial guarantees for uncompleted work and financial commitments. The terms of these guarantees vary with end dates ranging from the current fiscal year through the completion of such transactions and would typically be triggered in the event of nonperformance. Performance under the guarantees, if required, would not have a material effect on the Company's financial position, results of operations or cash flows. The Company offers warranties to its customers depending upon the specific product and terms of the customer purchase agreement. A typical warranty program requires that the Company replace defective products within a specified time period from the date of sale. The Company records an estimate for future warranty-related costs based on actual historical return rates and other known factors. Based on analysis of return rates and other factors, the Company’s warranty provisions are adjusted as necessary. The Company monitors its warranty activity and adjusts its reserve estimates when it is probable that future warranty costs will be different than those estimates. The Company’s product warranty liability for continuing operations is recorded in the consolidated statements of financial position in other current liabilities if the warranty is less than one year and in other noncurrent liabilities if the warranty extends longer than one year. The changes in the carrying amount of the Company’s total product warranty liability, including extended warranties for which deferred revenue is recorded, for the nine months ended June 30, 2018 and 2017 were as follows (in millions): Nine Months Ended 2018 2017 Balance at beginning of period $ 409 $ 374 Accruals for warranties issued during the period 225 221 Accruals from acquisition and divestitures 1 2 Accruals related to pre-existing warranties (24 ) (5 ) Settlements made (in cash or in kind) during the period (212 ) (199 ) Currency translation — (1 ) Balance at end of period $ 399 $ 392 As a result of the Tyco Merger in the fourth quarter of fiscal 2016, the Company recorded, as part of the acquired liabilities of Tyco, $290 million of post sale contingent tax indemnification liabilities which is generally recorded within other noncurrent liabilities in the consolidated statements of financial position. The liabilities are recorded at fair value and relate to certain tax related matters borne by the buyer of previously divested subsidiaries of Tyco which Tyco has indemnified certain parties and the amounts are probable of being paid. At June 30, 2018 and September 30, 2017, the Company recorded liabilities of $276 million and $290 million , respectively. Of the $276 million recorded as of June 30, 2018 , $235 million is related to prior divested businesses and the remainder relates to Tyco’s tax sharing agreements from its 2007 and 2012 spin-off transactions. These are certain guarantees or indemnifications extended among Tyco, Medtronic, TE Connectivity, ADT and Pentair in accordance with the terms of the 2007 and 2012 separation and tax sharing agreements.

Commitments and Contingencies

Commitments and Contingencies	9 Months Ended
	Jun. 30, 2018
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Environmental Matters The Company accrues for potential environmental liabilities when it is probable a liability has been incurred and the amount of the liability is reasonably estimable. As of June 30, 2018 , reserves for environmental liabilities totaled $43 million , of which $14 million was recorded within other current liabilities and $29 million was recorded within other noncurrent liabilities in the consolidated statements of financial position. Reserves for environmental liabilities totaled $51 million at September 30, 2017 , of which $10 million was recorded within other current liabilities and $41 million was recorded within other noncurrent liabilities in the consolidated statements of financial position. Such potential liabilities accrued by the Company do not take into consideration possible recoveries of future insurance proceeds. They do, however, take into account the likely share other parties will bear at remediation sites. It is difficult to estimate the Company’s ultimate level of liability at many remediation sites due to the large number of other parties that may be involved, the complexity of determining the relative liability among those parties, the uncertainty as to the nature and scope of the investigations and remediation to be conducted, the uncertainty in the application of law and risk assessment, the various choices and costs associated with diverse technologies that may be used in corrective actions at the sites, and the often quite lengthy periods over which eventual remediation may occur. Nevertheless, the Company does not currently believe that any claims, penalties or costs in connection with known environmental matters will have a material adverse effect on the Company’s financial position, results of operations or cash flows. In addition, the Company has identified asset retirement obligations for environmental matters that are expected to be addressed at the retirement, disposal, removal or abandonment of existing owned facilities. At June 30, 2018 and September 30, 2017 , the Company recorded conditional asset retirement obligations of $48 million and $61 million , respectively. Asbestos Matters The Company and certain of its subsidiaries, along with numerous other third parties, are named as defendants in personal injury lawsuits based on alleged exposure to asbestos containing materials. These cases have typically involved product liability claims based primarily on allegations of manufacture, sale or distribution of industrial products that either contained asbestos or were used with asbestos containing components. As of June 30, 2018 , the Company's estimated asbestos related net liability recorded on a discounted basis within the Company's consolidated statements of financial position was $180 million . The net liability within the consolidated statements of financial position was comprised of a liability for pending and future claims and related defense costs of $557 million , of which $54 million was recorded in other current liabilities and $503 million was recorded in other noncurrent liabilities. The Company also maintained separate cash, investments and receivables related to insurance recoveries within the consolidated statements of financial position of $377 million , of which $41 million was recorded in other current assets, and $336 million was recorded in other noncurrent assets. Assets included $10 million of cash and $274 million of investments, which have all been designated as restricted. In connection with the recognition of liabilities for asbestos-related matters, the Company records asbestos-related insurance recoveries that are probable; the amount of such recoveries recorded at June 30, 2018 was $93 million . As of September 30, 2017 , the Company's estimated asbestos related net liability recorded on a discounted basis within the Company's consolidated statements of financial position was $181 million . The net liability within the consolidated statements of financial position was comprised of a liability for pending and future claims and related defense costs of $573 million , of which $48 million was recorded in other current liabilities and $525 million was recorded in other noncurrent liabilities. The Company also maintained separate cash, investments and receivables related to insurance recoveries within the consolidated statements of financial position of $392 million , of which $53 million was recorded in other current assets, and $339 million was recorded in other noncurrent assets. Assets included $22 million of cash and $269 million of investments, which have all been designated as restricted. In connection with the recognition of liabilities for asbestos-related matters, the Company records asbestos-related insurance recoveries that are probable; the amount of such recoveries recorded at September 30, 2017 was $101 million . The Company's estimate of the liability and corresponding insurance recovery for pending and future claims and defense costs is based on the Company's historical claim experience, and estimates of the number and resolution cost of potential future claims that may be filed and is discounted to present value from 2068 (which is the Company's reasonable best estimate of the actuarially determined time period through which asbestos-related claims will be filed against Company affiliates). Asbestos related defense costs are included in the asbestos liability. The Company's legal strategy for resolving claims also impacts these estimates. The Company considers various trends and developments in evaluating the period of time (the look-back period) over which historical claim and settlement experience is used to estimate and value claims reasonably projected to be made through 2068. At least annually, the Company assesses the sufficiency of its estimated liability for pending and future claims and defense costs by evaluating actual experience regarding claims filed, settled and dismissed, and amounts paid in settlements. In addition to claims and settlement experience, the Company considers additional quantitative and qualitative factors such as changes in legislation, the legal environment, and the Company's defense strategy. The Company also evaluates the recoverability of its insurance receivable on an annual basis. The Company evaluates all of these factors and determines whether a change in the estimate of its liability for pending and future claims and defense costs or insurance receivable is warranted. The amounts recorded by the Company for asbestos-related liabilities and insurance-related assets are based on the Company's strategies for resolving its asbestos claims, currently available information, and a number of estimates and assumptions. Key variables and assumptions include the number and type of new claims that are filed each year, the average cost of resolution of claims, the identity of defendants, the resolution of coverage issues with insurance carriers, amount of insurance, and the solvency risk with respect to the Company's insurance carriers. Many of these factors are closely linked, such that a change in one variable or assumption will impact one or more of the others, and no single variable or assumption predominately influences the determination of the Company's asbestos-related liabilities and insurance-related assets. Furthermore, predictions with respect to these variables are subject to greater uncertainty in the later portion of the projection period. Other factors that may affect the Company's liability and cash payments for asbestos-related matters include uncertainties surrounding the litigation process from jurisdiction to jurisdiction and from case to case, reforms of state or federal tort legislation and the applicability of insurance policies among subsidiaries. As a result, actual liabilities or insurance recoveries could be significantly higher or lower than those recorded if assumptions used in the Company's calculations vary significantly from actual results. Insurable Liabilities The Company records liabilities for its workers' compensation, product, general, property and auto liabilities. The determination of these liabilities and related expenses is dependent on claims experience. For most of these liabilities, claims incurred but not yet reported are estimated by utilizing actuarial valuations based upon historical claims experience. At June 30, 2018 and September 30, 2017 , the insurable liabilities totaled $444 million and $445 million , respectively, of which $80 million and $122 million was recorded within other current liabilities, $25 million and $22 million was recorded within accrued compensation and benefits, and $339 million and $301 million was recorded within other noncurrent liabilities in the consolidated statements of financial position, respectively. The Company records receivables from third party insurers when recovery has been determined to be probable. The amount of such receivables recorded at June 30, 2018 was $21 million , of which $6 million was recorded within other current assets and $15 million was recorded within other noncurrent assets. The amount of such receivables recorded at September 30, 2017 was $46 million , of which $31 million was recorded within other current assets and $15 million was recorded within other noncurrent assets. The Company maintains captive insurance companies to manage certain of its insurable liabilities. Arbitration Award In September 2017, the Company was subject to an unfavorable arbitration award of approximately $50 million relating to a contractual dispute with a subcontractor used by the Company at an airport construction project in Doha, Qatar. In connection with the unfavorable arbitration award, the Company recorded a charge of $50 million within selling, general and administrative expenses in the consolidated statements of income in the fourth quarter of fiscal 2017. The airport project is being managed by a steering committee. The Company and the subcontractor were working jointly to document claims for increased costs against the steering committee when the subcontractor initiated the arbitration proceeding against the Company. Pursuant to its arbitration proceeding against the Company, the subcontractor sought to recover costs it alleges it incurred due to project delays, additional work and related financing costs. The Company has filed annulment proceedings with respect to the arbitration award in the local court in Qatar. While the award remains outstanding, a portion of the balance will accrue interest at a statutory rate of 9.56% . In a related action, the Company has initiated an arbitration claim against the steering committee related to costs it incurred in connection with delays of the airport construction project, including costs related to the above award. The arbitrator is expected to issue a decision on the Company’s claims against the steering committee by the end of fiscal 2018. Aqueous Film-Forming Foam ("AFFF") Litigation Two of our subsidiaries, Chemguard, Inc. ("Chemguard") and Tyco Fire Products L.P. ("Tyco Fire Products"), have been named, along with other defendant manufacturers, in a number of class action lawsuits relating to the use of fire-fighting foam products by the U.S. Department of Defense (the "DOD") and others for fire suppression purposes and related training exercises. Plaintiffs generally allege that the firefighting foam products manufactured by defendants contain or break down into the chemicals perfluorooctane sulfonate ("PFOS") and perfluorooctanoic acid ("PFOA") and that the use of these products by others at various airbases and airports resulted in the release of these chemicals into the environment and ultimately into communities’ drinking water supplies neighboring those airports and airbases. PFOA and PFOS are being studied by the United States Environmental Protection Agency (EPA) and other environmental and health agencies and researchers. The EPA has not issued regulatory limits, however; while those studies continue, the EPA has issued a health advisory level for PFOA and PFOS in drinking water. Both PFOA and PFOS are types of synthetic chemical compounds that have been present in firefighting foam. However, both are also present in many existing consumer products. According to EPA, PFOA and PFOS have been used to make carpets, clothing, fabrics for furniture, paper packaging for food and other materials (e.g., cookware) that are resistant to water, grease or stains. Plaintiffs generally seek compensatory damages, including damages for alleged personal injuries, medical monitoring, and alleged diminution in property values, and also seek punitive damages and injunctive relief to address remediation of the alleged contamination. As of August 2, 2018, the Company is named in 16 putative class actions in federal courts in six states as set forth below: Colorado • District of Colorado - Bell et al. v. The 3M Company et al., filed September 18, 2016. • District of Colorado - Bell et al. v. The 3M Company et al., filed September 18, 2016. • District of Colorado - Davis et al. v. The 3M Company et al., filed September 22, 2016. The above cases have been consolidated in the U.S. District Court for the District of Colorado, and a hearing on the plaintiffs’ motion for class certification is expected in 2018 with a trial date schedule for April 2019. Delaware • District of Delaware - Anderson v. The 3M Company et al. , filed June 12, 2018 in the United States District Court District of Delaware. Massachusetts • District of Massachusetts - Civitarese et al. v. The 3M Company et al., filed April 18, 2018 in the United States District Court of Massachusetts. Washington • Eastern District of Washington - Ackerman et al. v. The 3M Company et al., filed April 5, 2018 in the United States District Court, Eastern District of Washington. New York • Eastern District of New York - Green et al. v. The 3M Company et al., filed March 27, 2017 in Supreme Court of the State of New York, Suffolk County, prior to removal to federal court. • Southern District of New York - Adamo et al. v. The Port Authority of NY and NJ et al., filed August 11, 2017 in Supreme Court of the State of New York, Orange County, prior to removal to federal court. • Southern District of New York - Fogarty et al. v. The Port Authority of NY and NJ et al., filed August 11, 2017 in Supreme Court of the State of New York, Orange County, prior to removal to federal court. • Southern District of New York - Miller et al. v. The Port Authority of NY and NJ et al., filed August 11, 2017 in Supreme Court of the State of New York, Orange County, prior to removal to federal court. • Supreme Court of the State of New York, Suffolk County - Singer et al. v. The 3M Company et al., filed October 10, 2017. • Supreme Court of the State of New York, Suffolk County - Shipman et al. v. The 3M Company et al., filed March 21, 2018. Pennsylvania • Eastern District of Pennsylvania - Bates et al. v. The 3M Company et al., filed September 15, 2016. • Eastern District of Pennsylvania - Grande et al. v. The 3M Company et al., filed October 13, 2016. • Eastern District of Pennsylvania - Yockey et al. v. The 3M Company et al., filed October 24, 2016. • Eastern District of Pennsylvania - Fearnley et al. v. The 3M Company et al., filed December 9, 2016. The above cases have been consolidated in the U.S. District Court for the Eastern District of Pennsylvania. The defendants' motion to dismiss the complaint in the consolidated proceeding was denied without prejudice and the cases are currently stayed pending the appeal of an action in which the Company is not a party. In June 2018, the State of New York filed a lawsuit in New York state court ( State of New York v. 3M Co. , No. 904029-18 (N.Y. Sup. Ct., Albany County) against a number of manufacturers, including affiliates of the Company, with respect to alleged PFOS and PFOA contamination purportedly resulting from firefighting foams used at locations across New York, including Stewart Air National Guard Base in Newburgh and Gabreski Air National Guard Base in Southampton, Plattsburgh Air Force Base in Plattsburgh, Griffiss Air Force Base in Rome, and unspecified “other” sites throughout the State. The lawsuit seeks to recover costs and natural resource damages associated with contamination at these sites. In addition, as of August 2, 2018, there were a total of 51 individual or “mass” actions filed in state court in Colorado (41 cases), New York (1 case) and Pennsylvania (9 cases) against Chemguard and Tyco Fire Products and other defendants in which the plaintiffs generally seek compensatory damages, including damages for alleged personal injuries, medical monitoring, and alleged diminution in property values. The cases involve approximately 7,000 plaintiffs in Colorado, 26 plaintiffs in New York and 13 plaintiffs in Pennsylvania. The Company is also on notice of approximately 622 other possible individual product liability claims and 3 possible municipal claims by filings made in Pennsylvania state court, but complaints have not been filed in those matters, and, under Pennsylvania’s procedural rules, they may or may not result in lawsuits. Chemguard and Tyco Fire Products are also defendants in three municipal cases pending in the U.S. District Court for the District of Massachusetts: Town of Barnstable v. the 3M. Co., et al, (filed Nov. 21, 2016), County of Barnstable v. the 3M. Co., et al , (filed January 9, 2017) and City of Westfield v. the 3M Co., et al. , (filed on February 24, 2018), as well as two municipal cases pending in the Eastern District of New York: Suffolk County Water Auth. v. 3M Co. (filed November 30, 2017) and Hampton Bays Water Dist. v. 3M Co. (filed Feb. 21, 2018), and one municipal case pending in the Northern District of Florida: Emerald Coast Utilities Auth. v. 3M Co. (filed June 22, 2018). These municipal plaintiffs generally allege that the use of the defendants’ fire-fighting foam products at fire training academies, municipal airports, Air National Guard bases, or Navy bases released PFOS and PFOA into public water supply wells, allegedly requiring remediation of public property. The defendants have filed motions to dismiss in County of Barnstable and City of Westfield. In May 2018, the Company was also notified by the Widefield Water and Sanitation District in Colorado Springs, Colorado that it may assert claims regarding its remediation costs in connection with PFOS and PFOA contamination allegedly resulting from the use of those products at the Peterson Air Force Base. In addition, three water districts in Pennsylvania, Horsham Water and Sewer Authority, Warminster Municipal Authority, and Warrington Township have filed praecipes for summons against Chemguard and Tyco Fire Products and other AFFF manufacturers relating to alleged PFOS and PFOA contamination. These praecipes are not active suits, but have the effect of tolling the statute of limitations. Other AFFF Matters Tyco Fire Products, in coordination with the Wisconsin Department of Natural Resources (WDNR) and the Wisconsin Department of Health Services (DHS), has been conducting an environmental assessment of its Fire Technology Center (FTC) located in Marinette, Wisconsin and surrounding areas in the City of Marinette and Town of Peshtigo, Wisconsin. In connection with the assessment, PFOS and PFOA have been detected at the FTC and in groundwater and surface water outside of the boundaries of the FTC. Tyco Fire Products continues to investigate the extent of potential migration of these compounds and is working closely with WDNR and DHS to develop interim measures to remove these compounds from certain areas where they have been detected. The Company is vigorously defending these cases and believes that it has meritorious defenses to class certification and the claims asserted. However, there are numerous factual and legal issues to be resolved in connection with these claims, and it is extremely difficult to predict the outcome or ultimate financial exposure, if any, represented by these matters, but there can be no assurance that any such exposure will not be material. The Company is also pursuing insurance coverage for these matters. The Company is involved in various lawsuits, claims and proceedings incident to the operation of its businesses, including those pertaining to product liability, environmental, safety and health, intellectual property, employment, commercial and contractual matters, and various other casualty matters. Although the outcome of litigation cannot be predicted with certainty and some lawsuits, claims or proceedings may be disposed of unfavorably to us, it is management’s opinion that none of these will have a material adverse effect on the Company’s financial position, results of operations or cash flows. Costs related to such matters were not material to the periods presented.

Related Party Transactions (Not

Related Party Transactions (Notes)	9 Months Ended
	Jun. 30, 2018
Related Party Transactions [Abstract]
Related Party Transactions	Related Party Transactions In the ordinary course of business, the Company enters into transactions with related parties, such as equity affiliates. Such transactions consist of facility management services, the sale or purchase of goods and other arrangements. The net sales to and purchases from related parties included in the consolidated statements of income were $256 million and $45 million , respectively, for the three months ended June 30, 2018 ; and $251 million and $64 million , respectively, for the three months ended June 30, 2017 . The net sales to and purchases from related parties included in the consolidated statements of income were $720 million and $137 million , respectively, for the nine months ended June 30, 2018 ; and $705 million and $165 million , respectively, for the nine months ended June 30, 2017 . The following table sets forth the amount of accounts receivable due from and payable to related parties in the consolidated statements of financial position (in millions): June 30, 2018 September 30, 2017 Receivable from related parties $ 109 $ 108 Payable to related parties 51 50 The Company has also provided financial support to certain of its VIE's; see Note 1, "Financial Statements," of the notes to consolidated financial statements for additional information.

Financial Statements (Tables)

Financial Statements (Tables)	9 Months Ended
	Jun. 30, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Carrying Amounts and Classification of Assets and Liabilities for Consolidated VIEs	The carrying amounts and classification of assets (none of which are restricted) and liabilities included in the Company’s consolidated statements of financial position for the consolidated VIE is as follows (in millions): September 30, 2017 Current assets $ 2 Noncurrent assets 53 Total assets $ 55 Current liabilities $ 6 Noncurrent liabilities 42 Total liabilities $ 48

Discontinued Operations (Tables

Discontinued Operations (Tables)	9 Months Ended
	Jun. 30, 2018
Disposal Group, Held-for-sale or Disposed of by Sale, Not Discontinued Operations [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal Groups, Including Discontinued Operations [Table Text Block]	The following table summarizes the carrying value of the Scott Safety assets and liabilities held for sale at September 30, 2017 (in millions): September 30, 2017 Cash $ 9 Accounts receivable - net 100 Inventories 75 Other current assets 5 Assets held for sale $ 189 Property, plant and equipment - net $ 79 Goodwill 1,248 Other intangible assets - net 592 Other noncurrent assets 1 Noncurrent assets held for sale $ 1,920 Accounts payable $ 37 Accrued compensation and benefits 10 Other current liabilities 25 Liabilities held for sale $ 72 Other noncurrent liabilities $ 173 Noncurrent liabilities held for sale $ 173
Adient | Discontinued Operations, Disposed of by Means Other than Sale, Spinoff [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal Group, Including Discontinued Operations, Income Statement Disclosures [Table Text Block]	The following table summarizes the results of Adient, reclassified as discontinued operations for the nine month period ended June 30, 2017 (in millions). As the Adient spin-off occurred on October 31, 2016, there is only one month of Adient results included in the nine month period ended June 30, 2017 . Nine Months Ended 2017 Net sales $ 1,434 Income from discontinued operations before income taxes 1 Provision for income taxes on discontinued operations 35 Income from discontinued operations attributable to noncontrolling interests, net of tax 9 Loss from discontinued operations $ (43 )
Disposal Groups, Including Discontinued Operations [Table Text Block]	The following table summarizes depreciation and amortization, capital expenditures, and significant operating and investing noncash items related to Adient for the nine month period ended June 30, 2017 (in millions): Nine Months Ended 2017 Depreciation and amortization $ 29 Equity in earnings of partially-owned affiliates (31 ) Deferred income taxes 562 Equity-based compensation 1 Accrued income taxes (808 ) Capital expenditures (91 )

Inventories (Tables)

Inventories (Tables)	9 Months Ended
	Jun. 30, 2018
Inventory Disclosure [Abstract]
Inventories	Inventories consisted of the following (in millions): June 30, 2018 September 30, 2017 Raw materials and supplies $ 953 $ 919 Work-in-process 578 567 Finished goods 1,978 1,723 Inventories $ 3,509 $ 3,209

Goodwill and Other Intangible31

Goodwill and Other Intangible Assets (Tables)	9 Months Ended
	Jun. 30, 2018
Goodwill and Intangible Assets Disclosure [Abstract]
Changes in Carrying Amount of Goodwill	The changes in the carrying amount of goodwill in each of the Company’s reportable segments for the nine month period ended June 30, 2018 were as follows (in millions): Business Acquisitions Business Divestitures Currency Translation and Other September 30, June 30, 2017 2018 Building Technologies & Solutions Building Solutions North America $ 9,637 $ — $ — $ (45 ) $ 9,592 Building Solutions EMEA/LA 2,012 — — (53 ) 1,959 Building Solutions Asia Pacific 1,255 — — 2 1,257 Global Products 5,687 12 (20 ) (70 ) 5,609 Power Solutions 1,097 — — (2 ) 1,095 Total $ 19,688 $ 12 $ (20 ) $ (168 ) $ 19,512
Other Intangible Assets	The Company’s other intangible assets, primarily from business acquisitions valued based on independent appraisals, consisted of (in millions): June 30, 2018 September 30, 2017 Gross Carrying Amount Accumulated Amortization Net Gross Carrying Amount Accumulated Amortization Net Amortized intangible assets Technology $ 1,326 $ (233 ) $ 1,093 $ 1,328 $ (137 ) $ 1,191 Customer relationships 3,091 (605 ) 2,486 3,168 (486 ) 2,682 Miscellaneous 457 (181 ) 276 389 (147 ) 242 Total amortized intangible assets 4,874 (1,019 ) 3,855 4,885 (770 ) 4,115 Unamortized intangible assets Trademarks/trade names 2,447 — 2,447 2,483 — 2,483 Miscellaneous 122 — 122 143 — 143 2,569 — 2,569 2,626 — 2,626 Total intangible assets $ 7,443 $ (1,019 ) $ 6,424 $ 7,511 $ (770 ) $ 6,741

Significant Restructuring Cos32

Significant Restructuring Costs Change in Restructuring Reserve - 2018 Restructuring Plan (Tables)	9 Months Ended
	Jun. 30, 2018
2018 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Schedule of Restructuring Reserve by Type of Cost [Table Text Block]	The following table summarizes the changes in the Company’s 2018 Plan reserve, included within other current liabilities in the consolidated statements of financial position (in millions): Employee Severance and Termination Benefits Long-Lived Asset Impairments Other Total Original reserve $ 125 $ 30 $ 3 $ 158 Utilized—noncash — (30 ) — (30 ) Balance at December 31, 2017 $ 125 $ — $ 3 $ 128 Utilized—cash (8 ) — (1 ) (9 ) Balance at March 31, 2018 $ 117 $ — $ 2 $ 119 Utilized—cash (12 ) — (1 ) (13 ) Balance at June 30, 2018 $ 105 $ — $ 1 $ 106

Significant Restructuring Cos33

Significant Restructuring Costs Changes in Restructuring Reserve - 2017 Restructuring Plan (Tables)	9 Months Ended
	Jun. 30, 2018
2017 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Schedule of Restructuring Reserve by Type of Cost [Table Text Block]	The following table summarizes the changes in the Company’s 2017 Plan reserve, included within other current liabilities in the consolidated statements of financial position (in millions): Employee Severance and Termination Benefits Long-Lived Asset Impairments Other Currency Total Original reserve $ 276 $ 77 $ 14 $ — $ 367 Utilized—cash (75 ) — — — (75 ) Utilized—noncash — (77 ) (1 ) — (78 ) Adjustment to restructuring reserves 25 — — — 25 Balance at September 30, 2017 $ 226 $ — $ 13 $ — $ 239 Utilized—cash (142 ) — (4 ) — (146 ) Utilized—noncash — — — (1 ) (1 ) Balance at June 30, 2018 $ 84 $ — $ 9 $ (1 ) $ 92

Significant Restructuring Cos34

Significant Restructuring Costs Changes in Restructuring Reserve - 2016 Restructuring Plan (Tables)	9 Months Ended
	Jun. 30, 2018
2016 Restructuring Plan [Member]
Restructuring Cost and Reserve [Line Items]
Schedule of Restructuring Reserve by Type of Cost [Table Text Block]	The following table summarizes the changes in the Company’s 2016 Plan reserve, included within other current liabilities in the consolidated statements of financial position (in millions): Employee Severance and Termination Benefits Long-Lived Asset Impairments Other Currency Total Original reserve $ 368 $ 190 $ 62 $ — $ 620 Acquired Tyco restructuring reserves 78 — — — 78 Utilized—cash (32 ) — — — (32 ) Utilized—noncash — (190 ) (32 ) 1 (221 ) Balance at September 30, 2016 $ 414 $ — $ 30 $ 1 $ 445 Adient spin-off impact (194 ) — (22 ) — (216 ) Utilized—cash (86 ) — (2 ) — (88 ) Utilized—noncash — — — 1 1 Adjustment to restructuring reserves (25 ) — — — (25 ) Transfer to liabilities held for sale (3 ) — — — (3 ) Adjustment to acquired Tyco restructuring reserves (22 ) — — — (22 ) Balance at September 30, 2017 $ 84 $ — $ 6 $ 2 $ 92 Utilized—cash (16 ) — (2 ) — (18 ) Balance at June 30, 2018 $ 68 $ — $ 4 $ 2 $ 74

Income Taxes (Tables)

Income Taxes (Tables)	9 Months Ended
	Jun. 30, 2018
Income Tax Disclosure [Abstract]
Tax Jurisdictions and Years Currently under Audit Exam	In the U.S., fiscal years 2015 through 2016 are currently under exam by the Internal Revenue Service ("IRS"). Additionally, the Company is currently under exam in the following major non-U.S. jurisdictions: Tax Jurisdiction Tax Years Covered Belgium 2015 - 2016 China 2008 - 2016 France 2010 - 2012; 2015 - 2016 Germany 2007 - 2015 Spain 2010 - 2012 Switzerland 2011 - 2014 United Kingdom 2011 - 2015

Pension and Postretirement Pl36

Pension and Postretirement Plans (Tables)	9 Months Ended
	Jun. 30, 2018
Defined Benefit Plan [Abstract]
Components of Net Periodic Benefit Cost	The components of the Company’s net periodic benefit costs from continuing operations associated with its defined benefit pension and postretirement plans are shown in the tables below in accordance with ASC 715, "Compensation – Retirement Benefits" (in millions): U.S. Pension Plans Three Months Ended June 30, Nine Months Ended June 30, 2018 2017 2018 2017 Service cost $ 4 $ 4 $ 11 $ 13 Interest cost 27 28 80 85 Expected return on plan assets (58 ) (57 ) (172 ) (174 ) Net actuarial (gain) loss — 45 — (90 ) Settlement (gain) loss — 1 — (8 ) Net periodic benefit cost (credit) $ (27 ) $ 21 $ (81 ) $ (174 ) Non-U.S. Pension Plans Three Months Ended June 30, Nine Months Ended June 30, 2018 2017 2018 2017 Service cost $ 6 $ 8 $ 18 $ 24 Interest cost 14 13 43 36 Expected return on plan assets (29 ) (23 ) (87 ) (68 ) Net periodic benefit credit $ (9 ) $ (2 ) $ (26 ) $ (8 ) Postretirement Benefits Three Months Ended June 30, Nine Months Ended June 30, 2018 2017 2018 2017 Service cost $ — $ — $ 1 $ 1 Interest cost 2 1 5 4 Expected return on plan assets (2 ) (2 ) (7 ) (7 ) Net periodic benefit credit $ — $ (1 ) $ (1 ) $ (2 )

Debt and Financing Arrangemen37

Debt and Financing Arrangements (Tables)	9 Months Ended
	Jun. 30, 2018
Debt Disclosure [Abstract]
Components of Net Financing Charges	The Company's net financing charges line item in the consolidated statements of income for the three and nine months ended June 30, 2018 and 2017 contained the following components (in millions): Three Months Ended June 30, Nine Months Ended June 30, 2018 2017 2018 2017 Interest expense, net of capitalized interest costs $ 110 $ 115 $ 328 $ 343 Banking fees and bond cost amortization 14 14 41 55 Interest income (10 ) (4 ) (24 ) (16 ) Net foreign exchange results for financing activities (13 ) (1 ) (13 ) (6 ) Net financing charges $ 101 $ 124 $ 332 $ 376

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	9 Months Ended
	Jun. 30, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation, Activity [Table Text Block]	A summary of the stock-based awards granted during the nine month periods ended June 30, 2018 and 2017 is presented below: Nine Months Ended June 30, 2018 2017 Number Granted Weighted Average Grant Date Fair Value Number Granted Weighted Average Grant Date Fair Value Stock options 1,376,807 $ 7.04 2,841,686 $ 7.81 Stock appreciation rights — — 15,693 8.28 Restricted stock/units 2,188,131 37.26 1,671,677 41.75 Performance shares 496,478 36.31 846,725 48.40
Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block]	Nine Months Ended 2018 2017 Expected life of option (years) 6.5 4.75 & 6.5 Risk-free interest rate 2.28% 1.23% - 1.93% Expected volatility of the Company’s stock 23.7% 24.60% Expected dividend yield on the Company’s stock 2.78% 2.21%
Schedule of share-based payment award, performance share, valuation assumptions [Table Text Block]	Nine Months Ended 2018 2017 Risk-free interest rate 1.92% 1.40% Expected volatility of the Company’s stock 21.7% 21.0%

Earnings Per Share (Tables)

Earnings Per Share (Tables)	9 Months Ended
	Jun. 30, 2018
Earnings Per Share [Abstract]
Earnings Per Share	The following table reconciles the numerators and denominators used to calculate basic and diluted earnings per share (in millions): Three Months Ended June 30, Nine Months Ended June 30, 2018 2017 2018 2017 Income Available to Ordinary Shareholders Income from continuing operations $ 723 $ 555 $ 1,391 $ 779 Loss from discontinued operations — — — (43 ) Basic and diluted income available to shareholders $ 723 $ 555 $ 1,391 $ 736 Weighted Average Shares Outstanding Basic weighted average shares outstanding 925.6 935.4 926.0 937.2 Effect of dilutive securities: Stock options, unvested restricted stock and unvested performance share awards 5.1 9.0 6.1 9.6 Diluted weighted average shares outstanding 930.7 944.4 932.1 946.8 Antidilutive Securities Options to purchase shares 2.1 0.1 1.5 0.1

Equity and Noncontrolling Int40

Equity and Noncontrolling Interests (Tables)	9 Months Ended
	Jun. 30, 2018
Stockholders' Equity Note [Abstract]
Equity Attributable to Johnson Controls and Noncontrolling Interests	The following schedules present changes in consolidated equity attributable to Johnson Controls and noncontrolling interests (in millions, net of tax): Three Months Ended June 30, 2018 Three Months Ended June 30, 2017 Equity Attributable to Johnson Controls International plc Equity Attributable to Noncontrolling Interests Total Equity Equity Attributable to Johnson Controls International plc Equity Attributable to Noncontrolling Interests Total Equity Beginning balance, March 31 $ 20,874 $ 1,006 $ 21,880 $ 19,388 $ 813 $ 20,201 Total comprehensive income: Net income 723 71 794 555 66 621 Foreign currency translation adjustments (557 ) (44 ) (601 ) 268 3 271 Realized and unrealized gains (losses) on derivatives 3 (1 ) 2 (7 ) (1 ) (8 ) Realized and unrealized losses on marketable securities — — — (3 ) — (3 ) Other comprehensive income (loss) (554 ) (45 ) (599 ) 258 2 260 Comprehensive income 169 26 195 813 68 881 Other changes in equity: Cash dividends—ordinary shares (240 ) — (240 ) (234 ) — (234 ) Repurchases of ordinary shares (56 ) — (56 ) (307 ) — (307 ) Change in noncontrolling interest share — 4 4 — 3 3 Other, including options exercised 26 — 26 71 — 71 Ending balance, June 30 $ 20,773 $ 1,036 $ 21,809 $ 19,731 $ 884 $ 20,615 Nine Months Ended June 30, 2018 Nine Months Ended June 30, 2017 Equity Attributable to Johnson Controls International plc Equity Attributable to Noncontrolling Interests Total Equity Equity Attributable to Johnson Controls International plc Equity Attributable to Noncontrolling Interests Total Equity Beginning balance, September 30, $ 20,447 $ 920 $ 21,367 $ 24,118 $ 972 $ 25,090 Total comprehensive income: Net income 1,391 132 1,523 736 127 863 Foreign currency translation adjustments (331 ) 3 (328 ) (150 ) (22 ) (172 ) Realized and unrealized gains (losses) on derivatives (2 ) 1 (1 ) (13 ) 1 (12 ) Realized and unrealized gains (losses) on marketable securities (2 ) — (2 ) 6 — 6 Other comprehensive income (loss) (335 ) 4 (331 ) (157 ) (21 ) (178 ) Comprehensive income 1,056 136 1,192 579 106 685 Other changes in equity: Cash dividends—ordinary shares (722 ) — (722 ) (705 ) — (705 ) Dividends attributable to noncontrolling interests — (43 ) (43 ) — (47 ) (47 ) Repurchases of ordinary shares (255 ) — (255 ) (426 ) — (426 ) Change in noncontrolling interest share — 23 23 — (9 ) (9 ) Adoption of ASU 2016-09 179 — 179 — — — Spin-off of Adient — — — (4,038 ) (138 ) (4,176 ) Other, including options exercised 68 — 68 203 — 203 Ending balance, June 30 $ 20,773 $ 1,036 $ 21,809 $ 19,731 $ 884 $ 20,615
Changes in Redeemable Noncontrolling Interests	The following schedules present changes in the redeemable noncontrolling interests (in millions): Three Months Ended June 30, 2018 2017 Beginning balance, March 31 $ 235 $ 168 Net income 10 8 Foreign currency translation adjustments (13 ) 14 Realized and unrealized losses on derivatives (1 ) (1 ) Ending balance, June 30 $ 231 $ 189 Nine Months Ended June 30, 2018 2017 Beginning balance, September 30 $ 211 $ 234 Net income 35 29 Foreign currency translation adjustments (3 ) 6 Realized and unrealized losses on derivatives (9 ) (1 ) Dividends (3 ) (43 ) Spin-off of Adient — (36 ) Ending balance, June 30 $ 231 $ 189
Changes in Accumulated Other Comprehensive Income, Net of Tax	The following schedules present changes in accumulated other comprehensive income ("AOCI") attributable to Johnson Controls (in millions, net of tax): Three Months Ended June 30, 2018 2017 Foreign currency translation adjustments ("CTA") Balance at beginning of period $ (255 ) $ (1,007 ) Aggregate adjustment for the period (net of tax effect of $0 and $(5)) (557 ) 268 Balance at end of period (812 ) (739 ) Realized and unrealized gains (losses) on derivatives Balance at beginning of period 1 14 Current period changes in fair value (net of tax effect of $1 and $(1)) 5 (1 ) Reclassification to income (net of tax effect of $(2) and $(5)) ** (2 ) (6 ) Balance at end of period 4 7 Realized and unrealized gains (losses) on marketable securities Balance at beginning of period 2 8 Current period changes in fair value (net of tax effect of $0 and $1) 1 (3 ) Reclassification to income (net of tax effect of $(1) and $0) *** (1 ) — Balance at end of period 2 5 Pension and postretirement plans Balance at beginning of period (2 ) (2 ) Other changes — — Balance at end of period (2 ) (2 ) Accumulated other comprehensive loss, end of period $ (808 ) $ (729 ) Nine Months Ended June 30, 2018 2017 CTA Balance at beginning of period $ (481 ) $ (1,152 ) Aggregate adjustment for the period (net of tax effect of $1 and $0) * (331 ) (150 ) Adient spin-off impact (net of tax effect of $0) — 563 Balance at end of period (812 ) (739 ) Realized and unrealized gains (losses) on derivatives Balance at beginning of period 6 4 Current period changes in fair value (net of tax effect of $2 and $3) 7 6 Reclassification to income (net of tax effect of $(4) and $(12)) ** (9 ) (19 ) Adient spin-off impact (net of tax effect of $0 and $6) — 16 Balance at end of period 4 7 Realized and unrealized gains (losses) on marketable securities Balance at beginning of period 4 (1 ) Current period changes in fair value (net of tax effect of $0 and $1) (1 ) 6 Reclassification to income (net of tax effect of $(1) and $0) *** (1 ) — Balance at end of period 2 5 Pension and postretirement plans Balance at beginning of period (2 ) (4 ) Adient spin-off impact (net of tax effect of $0) — 2 Balance at end of period (2 ) (2 ) Accumulated other comprehensive loss, end of period $ (808 ) $ (729 ) * During the nine months ended June 30, 2018, $12 million of cumulative CTA was recognized as part of the divestiture-related gain recognized as part of the divestiture of Scott Safety. ** Refer to Note 15, "Derivative Instruments and Hedging Activities," of the notes to consolidated financial statements for disclosure of the line items in the consolidated statements of income affected by reclassifications from AOCI into income related to derivatives. ***During the nine months ended June 30, 2018, the Company sold certain marketable common stock for approximately $3 million . As a result, the Company recorded $2 million of realized gains within selling, general and administrative expenses.

Derivative Instruments and He41

Derivative Instruments and Hedging Activities (Tables)	9 Months Ended
	Jun. 30, 2018
Derivative Instruments [Line Items]
Outstanding Commodity Hedge Contracts	The Company had the following outstanding contracts to hedge forecasted commodity purchases (in metric tons): Volume Outstanding as of Commodity June 30, 2018 September 30, 2017 Copper 2,948 1,962 Polypropylene 8,540 19,563 Lead 31,009 24,705 Aluminum 3,885 2,169 Tin 2,276 1,715
Location and Fair Values of Derivative Instruments and Hedging Activities	The following table presents the location and fair values of derivative instruments and hedging activities included in the Company’s consolidated statements of financial position (in millions): Derivatives and Hedging Activities Designated as Hedging Instruments under ASC 815 Derivatives and Hedging Activities Not Designated as Hedging Instruments under ASC 815 June 30, September 30, June 30, September 30, 2018 2017 2018 2017 Other current assets Foreign currency exchange derivatives $ 8 $ 27 $ 11 $ — Commodity derivatives 2 9 — — Other noncurrent assets Equity swap — — 60 55 Total assets $ 10 $ 36 $ 71 $ 55 Other current liabilities Foreign currency exchange derivatives $ 7 $ 21 $ 22 $ 25 Commodity derivatives 3 1 — — Long-term debt Foreign currency denominated debt 2,916 2,058 — — Total liabilities $ 2,926 $ 2,080 $ 22 $ 25
Offsetting Assets and Liabilities	The gross and net amounts of derivative assets and liabilities were as follows (in millions): Fair Value of Assets Fair Value of Liabilities June 30, September 30, June 30, September 30, 2018 2017 2018 2017 Gross amount recognized $ 81 $ 91 $ 2,948 $ 2,105 Gross amount eligible for offsetting (18 ) (16 ) (18 ) (16 ) Net amount $ 63 $ 75 $ 2,930 $ 2,089
Location and Amount of Gains and Losses Gross of Tax on Derivative Instruments and Related Hedge Items	The following table presents the pre-tax gains (losses) recorded in other comprehensive income (loss) related to cash flow hedges for the three and nine months ended June 30, 2018 and 2017 (in millions): Derivatives in ASC 815 Cash Flow Hedging Relationships Three Months Ended June 30, Nine Months Ended June 30, 2018 2017 2018 2017 Foreign currency exchange derivatives $ 6 $ (3 ) $ 7 $ 3 Commodity derivatives — 1 2 6 Total $ 6 $ (2 ) $ 9 $ 9 The following tables present the location and amount of the pre-tax gains (losses) on cash flow hedges reclassified from AOCI into the Company’s consolidated statements of income for the three and nine months ended June 30, 2018 and 2017 (in millions): Derivatives in ASC 815 Cash Flow Hedging Relationships Location of Gain (Loss) Reclassified from AOCI into Income Three Months Ended June 30, Nine Months Ended June 30, 2018 2017 2018 2017 Foreign currency exchange derivatives Cost of sales $ 2 $ 8 $ 2 $ 24 Commodity derivatives Cost of sales 2 3 11 7 Total $ 4 $ 11 $ 13 $ 31 The following table presents the location and amount of pre-tax gains (losses) on fair value hedges recognized in the Company’s consolidated statements of income for the three and nine months ended June 30, 2018 and 2017 (in millions): Derivatives in ASC 815 Fair Value Hedging Relationships Location of Gain (Loss) Recognized in Income on Derivative Three Months Ended June 30, Nine Months Ended June 30, 2018 2017 2018 2017 Interest rate swap Net financing charges $ — $ — $ — $ (1 ) Fixed rate debt swapped to floating Net financing charges — — — 2 Total $ — $ — $ — $ 1 The following table presents the location and amount of pre-tax gains (losses) on derivatives not designated as hedging instruments recognized in the Company’s consolidated statements of income for the three and nine months ended June 30, 2018 and 2017 (in millions): Amount of Gain (Loss) Recognized in Income on Derivative Derivatives Not Designated as Hedging Instruments under ASC 815 Location of Gain (Loss) Recognized in Income on Derivative Three Months Ended June 30, Nine Months Ended June 30, 2018 2017 2018 2017 Foreign currency exchange derivatives Cost of sales $ (4 ) $ (4 ) $ (6 ) $ (1 ) Foreign currency exchange derivatives Net financing charges (27 ) 51 (26 ) 60 Foreign currency exchange derivatives Income tax provision — 1 2 (2 ) Foreign currency exchange derivatives Income (loss) from discontinued operations — — — 5 Equity swap Selling, general and administrative (3 ) 2 (10 ) 2 Total $ (34 ) $ 50 $ (40 ) $ 64

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	9 Months Ended
	Jun. 30, 2018
Fair Value Disclosures [Abstract]
Assets and Liabilities Measured at Fair Value	The following tables present the Company’s fair value hierarchy for those assets and liabilities measured at fair value as of June 30, 2018 and September 30, 2017 (in millions): Fair Value Measurements Using: Total as of June 30, 2018 Quoted Prices in Active Markets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Other current assets Foreign currency exchange derivatives $ 19 $ — $ 19 $ — Commodity derivatives 2 — 2 — Exchange traded funds (fixed income) 1 14 14 — — Other noncurrent assets Investments in marketable common stock 4 4 — — Deferred compensation plan assets 97 97 — — Exchange traded funds (fixed income) 1 148 148 — — Exchange traded funds (equity) 1 112 112 — — Equity swap 60 60 — Total assets $ 456 $ 375 $ 81 $ — Other current liabilities Foreign currency exchange derivatives $ 29 $ — $ 29 $ — Commodity derivatives 3 — 3 — Total liabilities $ 32 $ — $ 32 $ — Fair Value Measurements Using: Total as of September 30, 2017 Quoted Prices in Active Markets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Other current assets Foreign currency exchange derivatives $ 27 $ — $ 27 $ — Commodity derivatives 9 — 9 — Exchange traded funds (fixed income) 1 14 14 — — Other noncurrent assets Investments in marketable common stock 10 10 — — Deferred compensation plan assets 92 92 — — Exchange traded funds (fixed income) 1 155 155 — — Exchange traded funds (equity) 1 100 100 — — Equity swap 55 — 55 — Total assets $ 462 $ 371 $ 91 $ — Other current liabilities Foreign currency exchange derivatives $ 46 $ — $ 46 $ — Commodity derivatives 1 — 1 — Total liabilities $ 47 $ — $ 47 $ —

Segment Information (Tables)

Segment Information (Tables)	9 Months Ended
	Jun. 30, 2018
Segment Reporting, Disclosure of Entity's Reportable Segments [Abstract]
Financial Information Related to Company's Reportable Segments	Financial information relating to the Company’s reportable segments is as follows (in millions): Net Sales Three Months Ended Nine Months Ended 2018 2017 2018 2017 Building Technologies & Solutions Building Solutions North America $ 2,246 $ 2,142 $ 6,355 $ 6,181 Building Solutions EMEA/LA 926 896 2,748 2,669 Building Solutions Asia Pacific 681 630 1,864 1,767 Global Products 2,429 2,406 6,250 6,214 6,282 6,074 17,217 16,831 Power Solutions 1,838 1,609 5,813 5,205 Total net sales $ 8,120 $ 7,683 $ 23,030 $ 22,036 Segment EBITA Three Months Ended Nine Months Ended 2018 2017 2018 2017 Building Technologies & Solutions Building Solutions North America $ 314 $ 290 $ 780 $ 741 Building Solutions EMEA/LA 96 100 242 238 Building Solutions Asia Pacific 97 85 242 215 Global Products 435 437 949 806 942 912 2,213 2,000 Power Solutions 310 304 1,008 996 Total 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 — (49 ) (158 ) (226 ) Net mark-to-market adjustments on pension plans — (45 ) — 90 Net financing charges (101 ) (124 ) (332 ) (376 ) Income from continuing operations before income taxes $ 910 $ 718 $ 2,009 $ 1,496

Guarantees (Tables)

Guarantees (Tables)	9 Months Ended
	Jun. 30, 2018
Guarantees [Abstract]
Changes in Carrying Amount of Product Warranty Liability	The changes in the carrying amount of the Company’s total product warranty liability, including extended warranties for which deferred revenue is recorded, for the nine months ended June 30, 2018 and 2017 were as follows (in millions): Nine Months Ended 2018 2017 Balance at beginning of period $ 409 $ 374 Accruals for warranties issued during the period 225 221 Accruals from acquisition and divestitures 1 2 Accruals related to pre-existing warranties (24 ) (5 ) Settlements made (in cash or in kind) during the period (212 ) (199 ) Currency translation — (1 ) Balance at end of period $ 399 $ 392

Related Party Transactions (Tab

Related Party Transactions (Tables)	9 Months Ended
	Jun. 30, 2018
Related Party Transactions [Abstract]
Schedule of Related Party Transactions [Table Text Block]	The following table sets forth the amount of accounts receivable due from and payable to related parties in the consolidated statements of financial position (in millions): June 30, 2018 September 30, 2017 Receivable from related parties $ 109 $ 108 Payable to related parties 51 50

Financial Statements - Carrying

Financial Statements - Carrying Amounts and Classification of Assets and Liabilities for Consolidated VIEs (Detail) - USD ($) $ in Millions	Jun. 30, 2018	Sep. 30, 2017
Variable Interest Entity [Line Items]
Current assets	$ 12,465	$ 12,292
Current liabilities	11,301	11,854
Long-term liabilities	$ 16,065	18,452
Variable Interest Entity, Primary Beneficiary [Member]
Variable Interest Entity [Line Items]
Current assets		2
Noncurrent assets		53
Total assets		55
Current liabilities		6
Long-term liabilities		42
Total liabilities		$ 48

Financial Statements - Addition

Financial Statements - Additional Information (Detail) $ in Millions	3 Months Ended	9 Months Ended		12 Months Ended
	Sep. 30, 2017USD ($)SegmentEntity	Jun. 30, 2018USD ($)SegmentEntity	Jun. 30, 2017Segment	Sep. 30, 2017USD ($)Entity	Sep. 30, 2012InterestInvestmentEntity	Oct. 31, 2016shares
Financial Statement Details [Line Items]
Number of Countries in which Entity Operates		150
Adient shares received per 10 shares of Johnson Controls shares | shares						1
Johnson Controls shares converted into one share of Adient | shares						10
Interest percentage minimum for investments in partially-owned affiliates to be accounted for by the equity method		20.00%
Number of VIEs where Company is Primary Beneficiary | Entity	1			1
Number of separate investments a pre-existing VIE was reorganized into | Entity					3
Additional interests acquired | InterestInvestment					2
Third party debt agreement		$ 157
Loans to partially-owned affiliates		38
Floor guarantee		$ 25
Number of VIEs in which Company was not primary beneficiary | Entity		3		2
Restricted Cash and Cash Equivalents	$ 31	$ 19		$ 31
Restricted Cash and Investments, Current	22	10		22
Restricted Cash and Cash Equivalents, Noncurrent	9	$ 9		9
Number of reportable segments | Segment		5
Variable Interest Entity, Not Primary Beneficiary [Member]
Financial Statement Details [Line Items]
Investment balance of the Company's nonconsolidated VIEs	$ 65	$ 42		$ 65
Power Solutions
Financial Statement Details [Line Items]
Number of VIEs where Company is Primary Beneficiary | Entity		1
Building Technologies & Solutions
Financial Statement Details [Line Items]
Number of reportable segments | Segment	4		5

New Accounting Standards Recent

New Accounting Standards Recently Adopted Accounting Pronouncements (Details) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2017	Jun. 30, 2018
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Deferred tax asset from stock options exercised and restricted stock vestings	$ 179
Minimum [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Description		10.00%
Maximum [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Description		15.00%

Acquisitions and Divestitures -

Acquisitions and Divestitures - Additional Information (Detail) $ in Millions	3 Months Ended				9 Months Ended
	Jun. 30, 2018USD ($)	Mar. 31, 2018USD ($)	Dec. 31, 2017USD ($)	Mar. 31, 2017USD ($)	Jun. 30, 2018USD ($)	Jun. 30, 2017USD ($)	Sep. 30, 2016USD ($)
Acquisitions And Discontinued Operations [Line Items]
Cash paid for business acquisition					$ 24	$ 6
Goodwill, Acquired During Period					12
Proceeds from business divestitures, net of cash divested					2,101	180
Reduction in goodwill related to business divestitures					20
Cash paid related to prior acquistions					0	75
Scott Safety business [Member]
Acquisitions And Discontinued Operations [Line Items]
Proceeds from business divestitures, net of cash divested			$ 2,000
Reduction in goodwill related to business divestitures			1,200
Gain on sale of Scott Safety business			114
Discontinued Operation, Gain (Loss) on Disposal of Discontinued Operation, Net of Tax			84
Business Divestitures, Not Specific [Member]
Acquisitions And Discontinued Operations [Line Items]
Proceeds from business divestitures, net of cash divested						52
Proceeds from Divestiture of Businesses						$ 4
Number Of Businesses Divested						1
Cash Divested from Deconsolidation						$ 5
Individually Immaterial Acquisitions
Acquisitions And Discontinued Operations [Line Items]
Cash paid for business acquisition						$ 6
Number of acquisitions						3
Purchase price, net of cash acquired						$ 9
Global Products | Business Divestitures, Not Specific [Member]
Acquisitions And Discontinued Operations [Line Items]
Proceeds from business divestitures, net of cash divested		$ 103
Reduction in goodwill related to business divestitures		20
Global Products | Individually Immaterial Acquisitions
Acquisitions And Discontinued Operations [Line Items]
Cash paid for business acquisition					24
Goodwill, Acquired During Period					12
Building Solutions EMEA/LA | ADT security business in South Africa [Member]
Acquisitions And Discontinued Operations [Line Items]
Proceeds from business divestitures, net of cash divested				$ 129
Reduction in goodwill related to business divestitures				$ 92
Power Solutions
Acquisitions And Discontinued Operations [Line Items]
Goodwill, Acquired During Period					0
Reduction in goodwill related to business divestitures					$ 0
Tyco International Holding S.a.r.L. (TSarL) [Member]
Acquisitions And Discontinued Operations [Line Items]
Repayments of Debt	$ 400	$ 26	$ 1,900
Long-term Debt							$ 4,000

Discontinued Operations Discont

Discontinued Operations Discontinued Operations, Income Statement Disclosures (Details) - 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	Oct. 31, 2016
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Adient shares received per 10 shares of Johnson Controls shares								1
Johnson Controls shares converted into one share of Adient								10
Income from discontinued operations attributable to noncontrolling interests	$ 0		$ 0			$ 0	$ 9
Loss from discontinued operations	$ 0		0			$ 0	$ (43)
U.S. federal statutory income tax rate		21.00%					35.00%
Effective Income Tax Rate Reconciliation, Other Adjustments, Amount			$ 18	$ (8)	$ (46)
Discontinued Operations, Disposed of by Means Other than Sale, Spinoff [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net sales							$ 1,434
Income from discontinued operations before income taxes							1
Provision for income taxes on discontinued operations							35
Income from discontinued operations attributable to noncontrolling interests							9
Loss from discontinued operations							(43)
Separation costs							$ 79

Discontinued Operations Disco51

Discontinued Operations Discontinued Operations, Alternative Cash Flow Information - Adient spin-off (Details) - USD ($) $ in Millions	9 Months Ended
	Jun. 30, 2018	Jun. 30, 2017
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Depreciation and amortization	$ 844	$ 919
Equity in earnings of partially-owned affiliates	(111)	(166)
Deferred income taxes	(75)	1,056
Equity-based compensation	86	114
Accrued income taxes	167	(2,002)
Capital expenditures	$ (782)	(996)
Adient | Discontinued Operations, Disposed of by Means Other than Sale, Spinoff [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Depreciation and amortization		29
Equity in earnings of partially-owned affiliates		(31)
Deferred income taxes		562
Equity-based compensation		1
Accrued income taxes		(808)
Capital expenditures		$ (91)

Discontinued Operations Disposa

Discontinued Operations Disposal Group - Assets Held For Sale (Details) - USD ($) $ in Millions	Jun. 30, 2018	Sep. 30, 2017
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Assets held for sale	$ 12	$ 189
Noncurrent assets held for sale	0	1,920
Liabilities held for sale	0	72
Noncurrent liabilities held for sale	0	173
Global Products | Scott Safety business [Member] | Disposal Group, Held-for-sale, Not Discontinued Operations [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Cash		9
Accounts receivable - net		100
Inventories		75
Other current assets		5
Assets held for sale		189
Property, plant and equipment - net		79
Goodwill		1,248
Other intangible assets - net		592
Other noncurrent assets		1
Noncurrent assets held for sale		1,920
Accounts payable		37
Accrued compensation and benefits		10
Other current liabilities		25
Liabilities held for sale		72
Other noncurrent liabilities		173
Noncurrent liabilities held for sale		$ 173
Corporate Segment | Disposal Group, Held-for-sale, Not Discontinued Operations [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Assets held for sale	$ 12

Percentage-of-Completion Cont53

Percentage-of-Completion Contracts (Detail) - USD ($) $ in Millions	Jun. 30, 2018	Sep. 30, 2017
Disclosure Percentage Of Completion Contracts Additional Information [Abstract]
Costs and earnings in excess of billings related to contracts	$ 1,025	$ 908
Billing in excess of costs and earnings on uncompleted contracts	$ 545	$ 451

Inventories - Schedule of Inven

Inventories - Schedule of Inventories (Detail) - USD ($) $ in Millions	Jun. 30, 2018	Sep. 30, 2017
Inventory Disclosure [Abstract]
Raw materials and supplies	$ 953	$ 919
Work-in-process	578	567
Finished goods	1,978	1,723
Inventories	$ 3,509	$ 3,209

Goodwill and Other Intangible55

Goodwill and Other Intangible Assets - Changes in Carrying Amount of Goodwill (Details) $ in Millions	9 Months Ended
	Jun. 30, 2018USD ($)
Goodwill [Roll Forward]
Beginning Balance	$ 19,688
Business Acquisitions	12
Business Divestitures	(20)
Currency Translation and Other	(168)
Ending Balance	19,512
Power Solutions
Goodwill [Roll Forward]
Beginning Balance	1,097
Business Acquisitions	0
Business Divestitures	0
Currency Translation and Other	(2)
Ending Balance	1,095
Building Technologies & Solutions | Building Solutions North America
Goodwill [Roll Forward]
Beginning Balance	9,637
Business Acquisitions	0
Business Divestitures	0
Currency Translation and Other	(45)
Ending Balance	9,592
Building Technologies & Solutions | Building Solutions EMEA/LA
Goodwill [Roll Forward]
Beginning Balance	2,012
Business Acquisitions	0
Business Divestitures	0
Currency Translation and Other	(53)
Ending Balance	1,959
Building Technologies & Solutions | Building Solutions Asia Pacific
Goodwill [Roll Forward]
Beginning Balance	1,255
Business Acquisitions	0
Business Divestitures	0
Currency Translation and Other	2
Ending Balance	1,257
Building Technologies & Solutions | Global Products
Goodwill [Roll Forward]
Beginning Balance	5,687
Business Acquisitions	12
Business Divestitures	(20)
Currency Translation and Other	(70)
Ending Balance	$ 5,609

Goodwill and Other Intangible56

Goodwill and Other Intangible Assets - Goodwill Additional Information (Details) $ in Millions	Sep. 30, 2017USD ($)
Building Solutions EMEA/LA
Goodwill [Line Items]
Accumulated goodwill impairment	$ 47

Goodwill and Other Intangible57

Goodwill and Other Intangible Assets - Other Intangible Assets (Details) - USD ($) $ in Millions	Jun. 30, 2018	Sep. 30, 2017
Intangible Assets [Line Items]
Gross carrying amount, total intangible assets	$ 7,443	$ 7,511
Net, Total Intangible Assets	6,424	6,741
Finite-Lived Intangible Assets, Gross [Abstract]
Gross Carrying Amount	4,874	4,885
Accumulated Amortization	(1,019)	(770)
Net, Total Amortized Intangible Assets	3,855	4,115
Indefinite-Lived Intangible Assets (Excluding Goodwill) [Abstract]
Carrying Amount, Gross and Net	2,569	2,626
Patented Technology
Finite-Lived Intangible Assets, Gross [Abstract]
Gross Carrying Amount	1,326	1,328
Accumulated Amortization	(233)	(137)
Net, Total Amortized Intangible Assets	1,093	1,191
Customer Relationships
Finite-Lived Intangible Assets, Gross [Abstract]
Gross Carrying Amount	3,091	3,168
Accumulated Amortization	(605)	(486)
Net, Total Amortized Intangible Assets	2,486	2,682
Miscellaneous
Finite-Lived Intangible Assets, Gross [Abstract]
Gross Carrying Amount	457	389
Accumulated Amortization	(181)	(147)
Net, Total Amortized Intangible Assets	276	242
Trademarks/trade names
Indefinite-Lived Intangible Assets (Excluding Goodwill) [Abstract]
Carrying Amount, Gross and Net	2,447	2,483
Miscellaneous
Indefinite-Lived Intangible Assets (Excluding Goodwill) [Abstract]
Carrying Amount, Gross and Net	$ 122	$ 143

Goodwill and Other Intangible58

Goodwill and Other Intangible Assets - Other Intangible Assets Additional Information (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Finite-Lived Intangible Assets [Line Items]
Amortization of intangible assets	$ 100	$ 108	$ 288	$ 383
Future amortization expense, 2019	388		388
Future amortization expense, 2020	380		380
Future amortization expense, 2021	371		371
Future amortization expense, 2022	365		365
Future amortization expense, 2023	$ 344		$ 344

Significant Restructuring Cos59

Significant Restructuring Costs Change in Restructuring Reserve - 2018 Restructuring Plan (Details) - USD ($) $ in Millions	3 Months Ended						9 Months Ended
	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Jun. 30, 2018	Jun. 30, 2017
Restructuring Cost and Reserve [Line Items]
Restructuring and impairment costs	$ 0		$ 158	$ 49	$ 99	$ 78	$ 158	$ 226
2018 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Restructuring and impairment costs			158				158
Restructuring Reserve, Settled without Cash			(30)
Restructuring Reserve	106	$ 119	128				106
Payments for Restructuring	(13)	(9)
Employee Severance | 2018 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Restructuring and impairment costs			125
Restructuring Reserve, Settled without Cash			0
Restructuring Reserve	105	117	125				105
Payments for Restructuring	(12)	(8)
Fixed Asset Impairment | 2018 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Restructuring and impairment costs			30
Restructuring Reserve, Settled without Cash			(30)
Restructuring Reserve	0	0	0				0
Payments for Restructuring	0	0
Other Restructuring | 2018 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Restructuring and impairment costs			3
Restructuring Reserve, Settled without Cash			0
Restructuring Reserve	1	2	$ 3				1
Payments for Restructuring	$ (1)	$ (1)
Global Products | 2018 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Restructuring and impairment costs							76
Building Solutions EMEA/LA | 2018 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Restructuring and impairment costs							32
Corporate Segment | 2018 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Restructuring and impairment costs							24
Building Solutions Asia Pacific | 2018 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Restructuring and impairment costs							14
Building Solutions North America | 2018 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Restructuring and impairment costs							8
Power Solutions | 2018 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Restructuring and impairment costs							$ 4

Significant Restructuring Cos60

Significant Restructuring Costs Change in Restructuring Reserve - 2017 Restructuring Plan (Details) - USD ($) $ in Millions	3 Months Ended					9 Months Ended		12 Months Ended
	Jun. 30, 2018	Dec. 31, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Jun. 30, 2018	Jun. 30, 2017	Sep. 30, 2017	Sep. 30, 2016
Restructuring Cost and Reserve [Line Items]
Restructuring and impairment costs	$ 0	$ 158	$ 49	$ 99	$ 78	$ 158	$ 226
2016 Restructuring Plan [Domain]
Restructuring Cost and Reserve [Line Items]
Restructuring and impairment costs									$ 288
2017 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Restructuring and impairment costs								$ 367
Payments for Restructuring						(146)		(75)
Restructuring Reserve, Settled without Cash						(1)		(78)
Adjustment to restructuring reserves								25
Restructuring Reserve	92					92		239
Employee Severance | 2017 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Restructuring and impairment costs								276
Payments for Restructuring						(142)		(75)
Restructuring Reserve, Settled without Cash						0		0
Adjustment to restructuring reserves								25
Restructuring Reserve	84					84		226
Fixed Asset Impairment | 2017 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Restructuring and impairment costs								77
Payments for Restructuring						0		0
Restructuring Reserve, Settled without Cash						0		(77)
Adjustment to restructuring reserves								0
Restructuring Reserve	0					0		0
Other Restructuring | 2017 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Restructuring and impairment costs								14
Payments for Restructuring						(4)		0
Restructuring Reserve, Settled without Cash						0		(1)
Adjustment to restructuring reserves								0
Restructuring Reserve	9					9		13
Currency Translation | 2017 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Restructuring and impairment costs								0
Payments for Restructuring						0		0
Restructuring Reserve, Settled without Cash						(1)		0
Adjustment to restructuring reserves								0
Restructuring Reserve	$ (1)					$ (1)		0
Corporate Segment | 2016 Restructuring Plan [Domain]
Restructuring Cost and Reserve [Line Items]
Restructuring and impairment costs									161
Corporate Segment | 2017 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Restructuring and impairment costs								166
Building Technologies & Solutions EMEA LA [Member] | 2017 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Restructuring and impairment costs								74
Building Solutions North America | 2017 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Restructuring and impairment costs								59
Power Solutions | 2016 Restructuring Plan [Domain]
Restructuring Cost and Reserve [Line Items]
Restructuring and impairment costs									66
Power Solutions | 2017 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Restructuring and impairment costs								20
Building Solutions Asia Pacific | 2017 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Restructuring and impairment costs								16
Global Products | 2016 Restructuring Plan [Domain]
Restructuring Cost and Reserve [Line Items]
Restructuring and impairment costs									$ 44
Global Products | 2017 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Restructuring and impairment costs								$ 32

Significant Restructuring Cos61

Significant Restructuring Costs Change in Restructuring Reserve - 2016 Restructuring Plan (Details) - USD ($) $ in Millions	3 Months Ended					9 Months Ended		12 Months Ended
	Jun. 30, 2018	Dec. 31, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Jun. 30, 2018	Jun. 30, 2017	Sep. 30, 2017	Sep. 30, 2016
Restructuring Cost and Reserve [Line Items]
Restructuring and impairment costs	$ 0	$ 158	$ 49	$ 99	$ 78	$ 158	$ 226
2016 Restructuring Plan [Domain]
Restructuring Cost and Reserve [Line Items]
Restructuring and impairment costs									$ 288
2016 Restructuring Plan [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and impairment costs									620
Restructuring Reserve	74					74		$ 92	445
Payments for Restructuring						(18)		(88)	(32)
Restructuring Reserve, Settled without Cash								1	(221)
Adjustment to restructuring reserves								(25)
Employee Severance | 2016 Restructuring Plan [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and impairment costs									368
Restructuring Reserve	68					68		84	414
Payments for Restructuring						(16)		(86)	(32)
Restructuring Reserve, Settled without Cash								0	0
Adjustment to restructuring reserves								(25)
Fixed Asset Impairment | 2016 Restructuring Plan [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and impairment costs									190
Restructuring Reserve	0					0		0	0
Payments for Restructuring						0		0	0
Restructuring Reserve, Settled without Cash								0	(190)
Adjustment to restructuring reserves								0
Other Restructuring | 2016 Restructuring Plan [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and impairment costs									62
Restructuring Reserve	4					4		6	30
Payments for Restructuring						(2)		(2)	0
Restructuring Reserve, Settled without Cash								0	(32)
Adjustment to restructuring reserves								0
Currency Translation | 2016 Restructuring Plan [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and impairment costs									0
Restructuring Reserve	2					2		2	1
Payments for Restructuring						0		0	0
Restructuring Reserve, Settled without Cash								1	1
Adjustment to restructuring reserves								0
Tyco merger [Member] | 2016 Restructuring Plan [Domain]
Restructuring Cost and Reserve [Line Items]
Restructuring and impairment costs									78
Restructuring Reserve	$ 56					$ 56
Restructuring Reserve, Settled without Cash								(22)
Tyco merger [Member] | Employee Severance | 2016 Restructuring Plan [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and impairment costs									78
Restructuring Reserve, Settled without Cash								(22)
Tyco merger [Member] | Fixed Asset Impairment | 2016 Restructuring Plan [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and impairment costs									0
Restructuring Reserve, Settled without Cash								0
Tyco merger [Member] | Other Restructuring | 2016 Restructuring Plan [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and impairment costs									0
Restructuring Reserve, Settled without Cash								0
Tyco merger [Member] | Currency Translation | 2016 Restructuring Plan [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and impairment costs									0
Restructuring Reserve, Settled without Cash								0
Building Solutions EMEA/LA | 2016 Restructuring Plan [Domain]
Restructuring Cost and Reserve [Line Items]
Restructuring and impairment costs									17
Corporate Segment | 2016 Restructuring Plan [Domain]
Restructuring Cost and Reserve [Line Items]
Restructuring and impairment costs									161
Power Solutions | 2016 Restructuring Plan [Domain]
Restructuring Cost and Reserve [Line Items]
Restructuring and impairment costs									66
Adient spin-off [Member] | Transfer To Held for Sale [Member] | 2016 Restructuring Plan [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve, Settled without Cash								(216)
Adient spin-off [Member] | Transfer To Held for Sale [Member] | Employee Severance | 2016 Restructuring Plan [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve, Settled without Cash								(194)
Adient spin-off [Member] | Transfer To Held for Sale [Member] | Fixed Asset Impairment | 2016 Restructuring Plan [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve, Settled without Cash								0
Adient spin-off [Member] | Transfer To Held for Sale [Member] | Other Restructuring | 2016 Restructuring Plan [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve, Settled without Cash								(22)
Adient spin-off [Member] | Transfer To Held for Sale [Member] | Currency Translation | 2016 Restructuring Plan [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve, Settled without Cash								0
Scott Safety business [Member] | Transfer To Held for Sale [Member] | 2016 Restructuring Plan [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve, Settled without Cash								(3)
Scott Safety business [Member] | Transfer To Held for Sale [Member] | Employee Severance | 2016 Restructuring Plan [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve, Settled without Cash								(3)
Scott Safety business [Member] | Transfer To Held for Sale [Member] | Fixed Asset Impairment | 2016 Restructuring Plan [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve, Settled without Cash								0
Scott Safety business [Member] | Transfer To Held for Sale [Member] | Other Restructuring | 2016 Restructuring Plan [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve, Settled without Cash								0
Scott Safety business [Member] | Transfer To Held for Sale [Member] | Currency Translation | 2016 Restructuring Plan [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve, Settled without Cash								$ 0
Adient | Discontinued Operations | 2016 Restructuring Plan [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and impairment costs									$ 332

Significant Restructuring Cos62

Significant Restructuring Costs - Additional Information (Detail) $ in Millions	3 Months Ended					9 Months Ended		30 Months Ended
	Jun. 30, 2018USD ($)EmployeesPlant	Dec. 31, 2017USD ($)	Jun. 30, 2017USD ($)	Mar. 31, 2017USD ($)	Dec. 31, 2016USD ($)	Jun. 30, 2018USD ($)EmployeesPlant	Jun. 30, 2017USD ($)	Mar. 31, 2018EmployeesPlant
Restructuring Cost and Reserve [Line Items]
Restructuring and impairment costs | $	$ 0	$ 158	$ 49	$ 99	$ 78	$ 158	$ 226
Number of employees to be severed								9,200
Number of employees severed	4,300					4,300
Number of plants to be closed | Plant								11
Plants closed | Plant	6					6
Building Technologies & Solutions
Restructuring Cost and Reserve [Line Items]
Number of employees to be severed								7,300
Number of plants to be closed | Plant								11
Corporate Segment
Restructuring Cost and Reserve [Line Items]
Number of employees to be severed								1,700
Power Solutions
Restructuring Cost and Reserve [Line Items]
Number of employees to be severed								200

Income Taxes - Additional Infor

Income Taxes - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended						9 Months Ended
	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Jun. 30, 2018	Jun. 30, 2017	Sep. 30, 2017
Income Taxes, Additional Information [Line Items]
Discrete non-cash tax charge			$ 101
Effective Income Tax Rate Reconciliation, Repatriation of Foreign Earnings, Amount			$ 305
Transition tax percentage cash assets			15.50%
Transition tax percentage, other property			8.00%
Effective income tax rate							22.00%	38.00%
U.S. federal statutory income tax rate			21.00%					35.00%
Gross tax effected unrecognized tax benefits									$ 2,173
Amount of unrecognized tax benefits which may impact effective tax rate									2,047
Total net accrued interest, net of tax benefit									$ 99
Estimated benefit to tax expense			$ 25
Restructuring and impairment costs	$ 0		158	$ 49	$ 99	$ 78	$ 158	$ 226
Effective Income Tax Rate Reconciliation, Other Adjustments, Amount				(18)	8	46
Net actuarial gain	0			(45)	18	117	$ 0	$ 90
Transaction and integration costs	51	$ 64	50	70	138	130
Effective Income Tax Rate Reconciliation, Nondeductible Expense, Restructuring Charges, Amount			$ (24)	15	20	14
Blended 2018 U.S. Effective Tax Rate [Member]
Income Taxes, Additional Information [Line Items]
U.S. federal statutory income tax rate			24.50%
Transaction and integration costs [Member]
Income Taxes, Additional Information [Line Items]
Effective Income Tax Rate Reconciliation, Other Adjustments, Amount	$ (6)	$ (9)	$ (7)	$ (11)	(31)	(11)
Change in Entity Status
Income Taxes, Additional Information [Line Items]
Effective Income Tax Rate Reconciliation, Other Adjustments, Amount						$ (101)
Outside basis difference of certain subsidiaries of the Scott Safety business [Domain]
Income Taxes, Additional Information [Line Items]
Effective Income Tax Rate Reconciliation, Other Adjustments, Amount					$ (457)
Scott Safety business [Member]
Income Taxes, Additional Information [Line Items]
Gain on sale of Scott Safety business			114
Tax effect of gain on sale of Scott Safety business			$ 30
IRELAND
Income Taxes, Additional Information [Line Items]
U.S. federal statutory income tax rate	12.50%						12.50%	12.50%

Income Taxes - Tax Jurisdiction

Income Taxes - Tax Jurisdictions and Years Currently under Audit Exam (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jun. 30, 2018	Dec. 31, 2017	Jun. 30, 2018
Income Tax Examination [Line Items]
Estimated benefit to tax expense		$ 25
UNITED STATES | Earliest tax year under exam
Income Tax Examination [Line Items]
Tax years currently under audit exam			2,015
UNITED STATES | Latest tax year under exam
Income Tax Examination [Line Items]
Tax years currently under audit exam			2,016
BELGIUM | Earliest tax year under exam
Income Tax Examination [Line Items]
Tax years currently under audit exam	2,015
BELGIUM | Latest tax year under exam
Income Tax Examination [Line Items]
Tax years currently under audit exam	2,016
CHINA | Earliest tax year under exam
Income Tax Examination [Line Items]
Tax years currently under audit exam	2,008
CHINA | Latest tax year under exam
Income Tax Examination [Line Items]
Tax years currently under audit exam	2,016
France | Tax Year 2010 [Member]
Income Tax Examination [Line Items]
Tax years currently under audit exam	2,010
France | Tax Year 2011 [Member]
Income Tax Examination [Line Items]
Tax years currently under audit exam	2,011
France | Tax Year 2012 [Member]
Income Tax Examination [Line Items]
Tax years currently under audit exam	2,012
France | Tax Year 2015 [Member]
Income Tax Examination [Line Items]
Tax years currently under audit exam	2,015
France | Tax Year 2016 [Member]
Income Tax Examination [Line Items]
Tax years currently under audit exam	2,016
Germany | Earliest tax year under exam
Income Tax Examination [Line Items]
Tax years currently under audit exam	2,007
Germany | Latest tax year under exam
Income Tax Examination [Line Items]
Tax years currently under audit exam	2,015
SPAIN | Earliest tax year under exam
Income Tax Examination [Line Items]
Tax years currently under audit exam	2,010
SPAIN | Latest tax year under exam
Income Tax Examination [Line Items]
Tax years currently under audit exam	2,012
SWITZERLAND | Earliest tax year under exam
Income Tax Examination [Line Items]
Tax years currently under audit exam	2,011
SWITZERLAND | Latest tax year under exam
Income Tax Examination [Line Items]
Tax years currently under audit exam	2,014
United Kingdom | Earliest tax year under exam
Income Tax Examination [Line Items]
Tax years currently under audit exam	2,011
United Kingdom | Latest tax year under exam
Income Tax Examination [Line Items]
Tax years currently under audit exam	2,015

Pension and Postretirement Pl65

Pension and Postretirement Plans - Components of Net Periodic Benefit Cost (Detail) - USD ($) $ in Millions	3 Months Ended				9 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Jun. 30, 2018	Jun. 30, 2017
Defined Benefit Plan Disclosure [Line Items]
Net actuarial (gain) loss	$ 0	$ 45	$ (18)	$ (117)	$ 0	$ (90)
Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Service cost	0	0			1	1
Interest cost	2	1			5	4
Expected return on plan assets	(2)	(2)			(7)	(7)
Net periodic benefit credit	0	(1)			(1)	(2)
UNITED STATES | Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	4	4			11	13
Interest cost	27	28			80	85
Expected return on plan assets	(58)	(57)			(172)	(174)
Net actuarial (gain) loss	0	45			0	(90)
Settlement (gain) loss	0	1			0	(8)
Net periodic benefit credit	(27)	21			(81)	(174)
Non-U.S. | Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	6	8			18	24
Interest cost	14	13			43	36
Expected return on plan assets	(29)	(23)			(87)	(68)
Net periodic benefit credit	$ (9)	$ (2)			$ (26)	$ (8)

Debt and Financing Arrangemen66

Debt and Financing Arrangements - Additional Information (Detail) € in Millions, $ in Millions	3 Months Ended				9 Months Ended
	Jun. 30, 2018USD ($)	Mar. 31, 2018USD ($)	Dec. 31, 2017USD ($)	Dec. 31, 2017EUR (€)	Jun. 30, 2017USD ($)	Sep. 30, 2017USD ($)	Sep. 30, 2016USD ($)
Debt Instrument [Line Items]
Transactions costs related to debt exchange offers					$ 17
Tyco International Holding S.a.r.L. (TSarL) [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Current Borrowing Capacity	$ 1,250					$ 1,000
Three Point Seven Five Percent Due 2018 [Member]
Debt Instrument [Line Items]
Repayments of Debt		$ 67
Interest Rate Terms		0.0375
150 million euro floating rate term loan maturing in September 2018 [Member]
Debt Instrument [Line Items]
Repayments of Debt | €				€ 150
Debt Instrument, Term			364 days	364 days
One Point Four Percent Due Two Thousand Eighteen
Debt Instrument [Line Items]
Repayments of Debt			$ 300
Interest Rate Terms			0.014	0.014
Unsecured Debt [Member] | Zero Point Zero Percent Due Two Thousand Twenty-One [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount | €				€ 750
Interest Rate Terms			0	0
Tyco International Holding S.a.r.L. (TSarL) [Member]
Debt Instrument [Line Items]
Repayments of Debt	$ 400	$ 26	$ 1,900
Long-term Debt							$ 4,000
Revolving Credit Facility [Member] | 250 million USD maturing in Mar 2019 [Member]
Debt Instrument [Line Items]
Debt Instrument, Term	364 days
Debt Instrument, Face Amount	$ 250
Revolving Credit Facility [Member] | 150 million USD maturing in Mar 2018 [Member]
Debt Instrument [Line Items]
Debt Instrument, Term		364 days
Line of Credit Facility, Borrowing Capacity, Expired		$ 150
Revolving Credit Facility [Member] | 150 million USD maturing in Feb 2018 [Member]
Debt Instrument [Line Items]
Debt Instrument, Term		364 days
Line of Credit Facility, Borrowing Capacity, Expired		$ 150
Revolving Credit Facility [Member] | 150 million USD maturing in Feb 2019 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount		$ 150
Revolving Credit Facility [Member] | 250 million USD maturing in Jan 2018 [Member]
Debt Instrument [Line Items]
Debt Instrument, Term		364 days
Line of Credit Facility, Borrowing Capacity, Expired		$ 250
Revolving Credit Facility [Member] | 200 million USD maturing in Jan 2019 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount		$ 200

Debt and Financing Arrangemen67

Debt and Financing Arrangements - Components of Net Financing Charges (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Debt Disclosure [Abstract]
Interest expense, net of capitalized interest costs	$ 110	$ 115	$ 328	$ 343
Banking fees and bond cost amortization	14	14	41	55
Interest income	(10)	(4)	(24)	(16)
Net foreign exchange results for financing activities	(13)	(1)	(13)	(6)
Net financing charges	$ 101	$ 124	$ 332	$ 376

Stock-Based Compensation (Detai

Stock-Based Compensation (Details) - $ / shares	9 Months Ended
	Jun. 30, 2018	Jun. 30, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected life of option (years)	6 years 182 days
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options, number granted	1,376,807	2,841,686
Stock options, weighted average grant date fair value	$ 7.04	$ 7.81
Risk free interest rate - minimum		1.23%
Risk free interest rate - maximum		1.93%
Risk-free interest rate	2.28%
Expected volatility of the Company's stock	23.70%	24.60%
Expected dividend yield on the Company's stock	2.78%	2.21%
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period	10 years
Stock options | Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	2 years
Expected life of option (years)		4 years 9 months
Stock options | Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	3 years
Expected life of option (years)		6 years 6 months
Stock appreciation rights
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity instruments other than options, number granted	0	15,693
Equity instruments other than options, weighted average grant date fair value	$ 0	$ 8.28
Restricted stock/units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	3 years
Equity instruments other than options, number granted	2,188,131	1,671,677
Equity instruments other than options, weighted average grant date fair value	$ 37.26	$ 41.75
Performance shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	3 years
Equity instruments other than options, number granted	496,478	846,725
Equity instruments other than options, weighted average grant date fair value	$ 36.31	$ 48.40
Risk-free interest rate	1.92%	1.40%
Expected volatility of the Company's stock	21.70%	21.00%

Earnings Per Share - Earnings P

Earnings Per Share - Earnings Per Share (Detail) - USD ($) shares in Millions, $ in Millions	3 Months Ended		9 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Earnings Per Share [Abstract]
Income from continuing operations	$ 723	$ 555	$ 1,391	$ 779
Loss from discontinued operations	0	0	0	(43)
Basic and diluted income available to shareholders	$ 723	$ 555	$ 1,391	$ 736
Weighted Average Shares Outstanding
Basic weighted average shares outstanding	925.6	935.4	926	937.2
Effect of dilutive securities:
Stock options, unvested restricted stock and unvested performance share awards	5.1	9	6.1	9.6
Diluted weighted average shares outstanding	930.7	944.4	932.1	946.8
Antidilutive Securities
Options to purchase shares	2.1	0.1	1.5	0.1

Earnings Per Share - Additional

Earnings Per Share - Additional Information (Detail) - $ / shares	3 Months Ended		9 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Earnings Per Share [Abstract]
Dividend declared	$ 0.26	$ 0.25	$ 0.78	$ 0.75

Equity and Noncontrolling Int71

Equity and Noncontrolling Interests - Equity Attributable to Johnson Controls and Noncontrolling Interests (Details) - USD ($) $ in Millions	3 Months Ended			9 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2016	Jun. 30, 2018	Jun. 30, 2017
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance				$ 20,447
Beginning balance				920
Beginning balance				21,367
Foreign currency translation adjustments	$ (614)	$ 285		(331)	$ (166)
Realized and unrealized gains (losses) on derivatives	1	(9)		(10)	(13)
Realized and unrealized gains (losses) on marketable securities	0	(3)		(2)	6
Other comprehensive income (loss)	(613)	273		(343)	(173)
Comprehensive income (loss) attributable to Johnson Controls	169	813		1,056	579
Comprehensive income attributable to noncontrolling interests	22	89		159	140
Total comprehensive income (loss)	191	902		1,215	719
Repurchase of ordinary shares	(56)	(307)		(255)	(426)
Ending balance	20,773			20,773
Ending balance	1,036			1,036
Ending balance	21,809			21,809
Net income attributable to Johnson Controls	723	555		1,391	736
Equity Attributable to Johnson Controls
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	20,874	19,388	$ 24,118	20,447	24,118
Foreign currency translation adjustments	(557)	268			(150)
Realized and unrealized gains (losses) on derivatives	3	(7)			(13)
Realized and unrealized gains (losses) on marketable securities	0	(3)			6
Other comprehensive income (loss)	(554)	258		(335)	(157)
Comprehensive income (loss) attributable to Johnson Controls	169	813		1,056	579
Cash dividends - ordinary shares	(240)	(234)		(722)	(705)
Noncontrolling Interest, Decrease from Distributions to Noncontrolling Interest Holders				0	0
Repurchase of ordinary shares	(56)	(307)		(255)	(426)
Change In noncontrolling interest share	0	0		0	0
New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets				179	0
Spin-off of Adient			(4,020)	0	(4,038)
Other, including options exercised	26	71		68	203
Ending balance	20,773	19,731		20,773	19,731
Net income attributable to Johnson Controls	723	555		1,391	736
Equity Attributable to Noncontrolling Interest
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	1,006	813	972	920	972
Income attributable to noncontrolling interests	71	66		132	127
Foreign currency translation adjustments	(44)	3		3	(22)
Realized and unrealized gains on derivatives	(1)	(1)		1	1
Realized and unrealized gains on marketable securities	0	0		0	0
Other comprehensive income (loss)	(45)	2		4	(21)
Comprehensive income attributable to noncontrolling interests	26	68		136	106
Cash dividends - ordinary shares	0	0		0	0
Noncontrolling Interest, Decrease from Distributions to Noncontrolling Interest Holders				(43)	(47)
Repurchase of ordinary shares	0	0		0	0
Change In noncontrolling interest share	4	3		23	(9)
New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets				0	0
Spin-off of Adient				0	(138)
Other, including options exercised	0	0		0	0
Ending balance	1,036	884		1,036	884
Total Equity Excluding Redeemable Noncontrolling Interest [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	21,880	20,201	$ 25,090	21,367	25,090
Net income	794	621		1,523	863
Foreign currency translation adjustments	(601)	271		(328)	(172)
Realized and unrealized gains (losses) on derivatives	2	(8)		(1)	(12)
Realized and unrealized gains (losses) on marketable securities	0	(3)		(2)	6
Other comprehensive income (loss)	(599)	260		(331)	(178)
Total comprehensive income (loss)	195	881		1,192	685
Cash dividends - ordinary shares	(240)	(234)		(722)	(705)
Noncontrolling Interest, Decrease from Distributions to Noncontrolling Interest Holders				(43)	(47)
Repurchase of ordinary shares	(56)	(307)		(255)	(426)
Change In noncontrolling interest share	4	3		(23)	9
New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets				179	0
Spin-off of Adient				0	4,176
Other, including options exercised	26	71		(68)	(203)
Ending balance	$ 21,809	$ 20,615		21,809	$ 20,615
Parent Company [Member] | Equity Attributable to Johnson Controls
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Foreign currency translation adjustments				(331)
Realized and unrealized gains (losses) on derivatives				(2)
Realized and unrealized gains (losses) on marketable securities				$ (2)

Equity and Noncontrolling Int72

Equity and Noncontrolling Interests Equity and Noncontrolling Interests - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended				9 Months Ended
	Jun. 30, 2018	Dec. 31, 2017	Jun. 30, 2017	Dec. 31, 2016	Jun. 30, 2018	Jun. 30, 2017	Sep. 30, 2016
Equity, Class of Treasury Stock [Line Items]
Deferred tax asset from stock options exercised and restricted stock vestings		$ 179
Stock repurchase program, authorized amount		$ 1,000
Treasury Stock, Value, Acquired, Cost Method	$ 56		$ 307		$ 255	$ 426
Stock Repurchase Program, Remaining Authorized Repurchase Amount	1,100				1,100
Post Merger Stock Repurchase Program [Member]
Equity, Class of Treasury Stock [Line Items]
Stock repurchase program, authorized amount							$ 1,000
Parent
Equity, Class of Treasury Stock [Line Items]
Stockholder's equity, spin-off of Adient				$ (4,020)	0	(4,038)
Treasury Stock, Value, Acquired, Cost Method	$ 56		$ 307		$ 255	$ 426

Equity and Noncontrolling Int73

Equity and Noncontrolling Interests - Changes in Redeemable Noncontrolling Interests (Details) - USD ($) $ in Millions	3 Months Ended			9 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2016	Jun. 30, 2018	Jun. 30, 2017
Parent
Stockholders' Equity Attributable to Redeemable Noncontrolling Interest [Roll Forward]
Spin-off of Adient			$ 4,020	$ 0	$ 4,038
Redeemable Noncontrolling Interests [Member]
Stockholders' Equity Attributable to Redeemable Noncontrolling Interest [Roll Forward]
Beginning balance	$ 235	$ 168	$ 234	211	234
Net income	10	8		35	29
Foreign currency translation adjustments	(13)	14		(3)	6
Realized and unrealized losses on derivatives	(1)	(1)		(9)	(1)
Dividends				(3)	(43)
Spin-off of Adient				0	(36)
Ending balance	$ 231	$ 189		$ 231	$ 189

Equity and Noncontrolling Int74

Equity and Noncontrolling Interests - Accumulated Other Comprehensive Income (Details) - USD ($) $ in Millions	3 Months Ended				9 Months Ended
	Jun. 30, 2018		Jun. 30, 2017		Jun. 30, 2018		Jun. 30, 2017		Sep. 30, 2017
Realized and unrealized gains (losses) on derivatives
Current period changes in fair value	$ 1		$ (9)		$ (10)		$ (13)
Realized and unrealized gains (losses) on marketable securities
Reclassification to income	(1)		0		(1)		0
Reclassification to income, tax effect	(1)				(1)
Pension and postretirement plans
Other changes	0		0
Accumulated other comprehensive loss	(808)		(729)		(808)		(729)		$ (473)
Proceeds from Sale and Maturity of Marketable Securities					3
Marketable Securities, Realized Gain (Loss)					2
Foreign currency translation adjustments
Foreign currency translation adjustments
Balance at beginning of period	(255)		(1,007)		(481)		(1,152)
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax, Portion Attributable to Parent	(557)		268		(331)		(150)
Adient spin-off impact					0		563
Balance at end of period	(812)		(739)		(812)		(739)
Aggregate adjustment for period, tax effect	0	[1]	(5)	[1]	1		0
Adient spin-off impact, tax effect					0		0
Realized and unrealized gains (losses) on derivatives
Realized and unrealized gains (losses) on derivatives
Balance at beginning of period	1		14		6		4
Current period changes in fair value	5		(1)		7		6
Reclassification to income	(2)		(6)		(9)		(19)
Adient spin-off impact					0		16
Balance at end of period	4		7		4		7
Current period changes in fair value, tax effect	1		(1)		2		3
Reclassifcation to income, tax effect	(2)	[2]	(5)	[2]	(4)	[1]	(12)	[1]
Adient spin-off, tax effect					0		6
Realized and unrealized gains (losses) on marketable securities
Realized and unrealized gains (losses) on marketable securities
Balance at beginning of period	2		8		4		(1)
Current period changes in fair value	1		(3)		(1)		6
Balance at end of period	2		5		2		5
Current period changes in fair value, tax effect	0		1		0		1
Pension and postretirement plans
Pension and postretirement plans
Balance at beginning of period	(2)		(2)		(2)		(4)
Adient spin-off impact					0		2
Balance at end of period	$ (2)		$ (2)		(2)		(2)
Adient spin-off, tax effect					0		$ 0
Scott Safety business [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Reclassification Adjustment from AOCI, Realized upon Sale or Liquidation, Net of Tax					$ 12
[1]	* During the nine months ended June 30, 2018, $12 million of cumulative CTA was recognized as part of the divestiture-related gain recognized as part of the divestiture of Scott Safety.
[2]	** Refer to Note 15, "Derivative Instruments and Hedging Activities," of the notes to consolidated financial statements for disclosure of the line items in the consolidated statements of income affected by reclassifications from AOCI into income related to derivatives.***During the nine months ended June 30, 2018, the Company sold certain marketable common stock for approximately $3 million. As a result, the Company recorded $2 million of realized gains within selling, general and administrative expenses.

Derivative Instruments and He75

Derivative Instruments and Hedging Activities - Location and Fair Values of Derivative Instruments and Hedging Activities (Detail) € in Millions, shares in Millions, $ in Millions, ¥ in Billions	3 Months Ended		9 Months Ended	12 Months Ended
	Jun. 30, 2018USD ($)TSwapshares	Dec. 31, 2016	Jun. 30, 2018USD ($)TSwap	Sep. 30, 2017USD ($)TSwapshares	Jun. 30, 2018EUR (€)TSwap	Jun. 30, 2018JPY (¥)TSwap	Sep. 30, 2017EUR (€)TSwap	Sep. 30, 2017JPY (¥)TSwap	Sep. 30, 2016USD ($)Swap
Derivative Instruments [Line Items]
Hedge Percentage For Foreign Exchange Transactional Exposures Minimum			70.00%
Hedge Percentage For Foreign Exchange Transactional Exposures Maximum			90.00%
Number of Interest Rate Derivatives Held | Swap	0		0	0	0	0	0	0
Number of interest rate derivatives terminated		4
Derivative, amount of hedged ordinary shares | shares	1.8			1.4
Derivative assets	$ 81		$ 81	$ 91
Derivative liabilities	$ 2,948		$ 2,948	$ 2,105
Copper [Member]
Derivative Instruments [Line Items]
Derivative, Nonmonetary Notional Amount | T	2,948		2,948	1,962	2,948	2,948	1,962	1,962
Polypropylene [Member]
Derivative Instruments [Line Items]
Derivative, Nonmonetary Notional Amount | T	8,540		8,540	19,563	8,540	8,540	19,563	19,563
Lead [Member]
Derivative Instruments [Line Items]
Derivative, Nonmonetary Notional Amount | T	31,009		31,009	24,705	31,009	31,009	24,705	24,705
Aluminum [Member]
Derivative Instruments [Line Items]
Derivative, Nonmonetary Notional Amount | T	3,885		3,885	2,169	3,885	3,885	2,169	2,169
Tin [Member]
Derivative Instruments [Line Items]
Derivative, Nonmonetary Notional Amount | T	2,276		2,276	1,715	2,276	2,276	1,715	1,715
Equity swap
Derivative Instruments [Line Items]
Derivative, Amount of Hedged Item	$ 73		$ 73	$ 58
Foreign Currency Denominated Debt [Member]
Derivative Instruments [Line Items]
Notional amount | ¥						¥ 35		¥ 35
Designated as Hedging Instrument
Derivative Instruments [Line Items]
Derivative assets	10		10	36
Derivative liabilities	2,926		2,926	2,080
Designated as Hedging Instrument | Other Current Assets | Foreign Currency Exchange Derivatives
Derivative Instruments [Line Items]
Derivative assets	8		8	27
Designated as Hedging Instrument | Other Current Assets | Commodity Derivatives
Derivative Instruments [Line Items]
Derivative assets	2		2	9
Designated as Hedging Instrument | Other Noncurrent Assets | Equity swap
Derivative Instruments [Line Items]
Derivative assets	0		0	0
Designated as Hedging Instrument | Other Current Liabilities | Foreign Currency Exchange Derivatives
Derivative Instruments [Line Items]
Derivative liabilities	7		7	21
Designated as Hedging Instrument | Other Current Liabilities | Commodity Derivatives
Derivative Instruments [Line Items]
Derivative liabilities	3		3	1
Designated as Hedging Instrument | Long-term Debt | Foreign Currency Denominated Debt [Member]
Derivative Instruments [Line Items]
Derivative liabilities	2,916		2,916	2,058
Not Designated as Hedging Instrument
Derivative Instruments [Line Items]
Derivative assets	71		71	55
Derivative liabilities	22		22	25
Not Designated as Hedging Instrument | Other Current Assets | Foreign Currency Exchange Derivatives
Derivative Instruments [Line Items]
Derivative assets	11		11	0
Not Designated as Hedging Instrument | Other Current Assets | Commodity Derivatives
Derivative Instruments [Line Items]
Derivative assets	0		0	0
Not Designated as Hedging Instrument | Other Noncurrent Assets | Equity swap
Derivative Instruments [Line Items]
Derivative assets	60		60	55
Not Designated as Hedging Instrument | Other Current Liabilities | Foreign Currency Exchange Derivatives
Derivative Instruments [Line Items]
Derivative liabilities	22		22	25
Not Designated as Hedging Instrument | Other Current Liabilities | Commodity Derivatives
Derivative Instruments [Line Items]
Derivative liabilities	0		0	0
Not Designated as Hedging Instrument | Long-term Debt | Foreign Currency Denominated Debt [Member]
Derivative Instruments [Line Items]
Derivative liabilities	$ 0		$ 0	$ 0
One Point Four Percent Due Two Thousand Eighteen | Interest Rate Swaps
Derivative Instruments [Line Items]
Number of Interest Rate Derivatives Held | Swap									3
Notional amount									$ 300
Debt Instrument, Interest Rate, Stated Percentage									1.40%
2.6% due 2017 | Interest Rate Swaps
Derivative Instruments [Line Items]
Number of Interest Rate Derivatives Held | Swap									4
Notional amount									$ 400
Debt Instrument, Interest Rate, Stated Percentage									2.60%
7.125% due 2017 | Interest Rate Swaps
Derivative Instruments [Line Items]
Number of Interest Rate Derivatives Held | Swap									1
Notional amount									$ 150
Debt Instrument, Interest Rate, Stated Percentage									7.125%
One billion euro net investment hedge [Member] | Foreign Currency Denominated Debt [Member]
Derivative Instruments [Line Items]
Notional amount | €					€ 1,000		€ 1,000
423 million euro net investment hedge [Member] | Foreign Currency Denominated Debt [Member]
Derivative Instruments [Line Items]
Notional amount | €					423		423
58 million euro net investment hedge [Member] | Foreign Currency Denominated Debt [Member]
Derivative Instruments [Line Items]
Notional amount | €					€ 58		€ 58

Derivative Instruments and He76

Derivative Instruments and Hedging Activities Derivative Instruments and Hedging Activities - Offsetting Assets and Liabilities (Details) - USD ($)	Jun. 30, 2018	Sep. 30, 2017
Offsetting Derivative Assets and Liabilities [Abstract]
Collateral Already Posted, Aggregate Fair Value	$ 0	$ 0
Derivative assets	81,000,000	91,000,000
Gross amount eligible for offsetting, derivative assets	(18,000,000)	(16,000,000)
Net derivative amount, derivative assets	63,000,000	75,000,000
Derivative liabilities	2,948,000,000	2,105,000,000
Gross amount eligible for offsetting, derivative liabilities	(18,000,000)	(16,000,000)
Net derivative amount, derivative liabilities	$ 2,930,000,000	$ 2,089,000,000

Derivative Instruments and He77

Derivative Instruments and Hedging Activities - Location and Amount of Gains and Losses on Derivative Instruments and Related Hedge Items (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Gain (Loss) Recognized in Income, Derivative not Recognized as Hedge	$ (34)	$ 50	$ (40)	$ 64
Foreign Currency Exchange Derivatives | Cost of Sales
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Gain (Loss) Recognized in Income, Derivative not Recognized as Hedge	(4)	(4)	(6)	(1)
Foreign Currency Exchange Derivatives | Discontinued Operations [Domain]
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Gain (Loss) Recognized in Income, Derivative not Recognized as Hedge	0	0	0	5
Foreign Currency Exchange Derivatives | Net Financing Charges
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Gain (Loss) Recognized in Income, Derivative not Recognized as Hedge	(27)	51	(26)	60
Foreign Currency Exchange Derivatives | Provision For Income Tax [Member]
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Gain (Loss) Recognized in Income, Derivative not Recognized as Hedge	0	1	2	(2)
Equity swap | Selling, General And Administrative
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Gain (Loss) Recognized in Income, Derivative not Recognized as Hedge	(3)	2	(10)	2
Net Investment Hedging [Member]
Cash Flow Hedges Derivative Instruments at Fair Value, Net [Abstract]
Derivative Instruments, Gain (Loss) Recognized in Other Comprehensive Income (Loss), Effective Portion, Net	165	(105)	29	(77)
Cash Flow Hedging
Cash Flow Hedges Derivative Instruments at Fair Value, Net [Abstract]
Derivative Instruments, Gain (Loss) Recognized in Other Comprehensive Income (Loss), Effective Portion, Net	6	(2)	9	9
Amount of Gain (Loss) Reclassified from AOCI into Income	4	11	13	31
Cash Flow Hedging | Foreign Currency Exchange Derivatives
Cash Flow Hedges Derivative Instruments at Fair Value, Net [Abstract]
Derivative Instruments, Gain (Loss) Recognized in Other Comprehensive Income (Loss), Effective Portion, Net	6	(3)	7	3
Cash Flow Hedging | Foreign Currency Exchange Derivatives | Cost of Sales
Cash Flow Hedges Derivative Instruments at Fair Value, Net [Abstract]
Amount of Gain (Loss) Reclassified from AOCI into Income	2	8	2	24
Cash Flow Hedging | Commodity Derivatives
Cash Flow Hedges Derivative Instruments at Fair Value, Net [Abstract]
Derivative Instruments, Gain (Loss) Recognized in Other Comprehensive Income (Loss), Effective Portion, Net	0	1	2	6
Cash Flow Hedging | Commodity Derivatives | Cost of Sales
Cash Flow Hedges Derivative Instruments at Fair Value, Net [Abstract]
Amount of Gain (Loss) Reclassified from AOCI into Income	2	3	11	7
Fair Value Hedging
Fair Value Hedge [Abstract]
Gain (Loss) Recognized in Income, Fair Value Hedge	0	0	0	1
Fair Value Hedging | Interest Rate Swaps | Net Financing Charges
Fair Value Hedge [Abstract]
Gain (Loss) Recognized in Income, Fair Value Hedge	0	0	0	(1)
Fair Value Hedging | Fixed Rate Debt Swapped to Floating | Net Financing Charges
Fair Value Hedge [Abstract]
Gain (Loss) Recognized in Income, Fair Value Hedge	$ 0	$ 0	$ 0	$ 2

Derivative Instruments and He78

Derivative Instruments and Hedging Activities - Additional Information (Detail) € in Millions, ¥ in Billions	3 Months Ended		9 Months Ended
	Jun. 30, 2018USD ($)	Jun. 30, 2017USD ($)	Jun. 30, 2018USD ($)	Jun. 30, 2017USD ($)	Jun. 30, 2018EUR (€)	Jun. 30, 2018JPY (¥)	Sep. 30, 2017EUR (€)	Sep. 30, 2017JPY (¥)
Derivative [Line Items]
Gains (losses) reclassified from CTA to income for the Company's outstanding net investment hedges | $	$ 0	$ 0	$ 0	$ 0
Foreign Currency Denominated Debt [Member]
Derivative [Line Items]
Notional amount | ¥						¥ 35		¥ 35
58 million euro net investment hedge [Member] | Foreign Currency Denominated Debt [Member]
Derivative [Line Items]
Notional amount					€ 58		€ 58
One billion euro net investment hedge [Member] | Foreign Currency Denominated Debt [Member]
Derivative [Line Items]
Notional amount					1,000		1,000
750 million euro net investment hedge [Member] | Foreign Currency Denominated Debt [Member]
Derivative [Line Items]
Notional amount					750
423 million euro net investment hedge [Member] | Foreign Currency Denominated Debt [Member]
Derivative [Line Items]
Notional amount					€ 423		€ 423
Net Investment Hedging [Member]
Derivative [Line Items]
Derivative Instruments, Gain (Loss) Recognized in Other Comprehensive Income (Loss), Effective Portion, Net | $	$ 165,000,000	$ (105,000,000)	$ 29,000,000	$ (77,000,000)

Fair Value Measurements - Asset

Fair Value Measurements - Assets and Liabilities Measured at Fair Value (Detail) - USD ($) $ in Millions		Jun. 30, 2018	Sep. 30, 2017
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets		$ 81	$ 91
Derivative liabilities		2,948	2,105
Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets		456	462
Total liabilities		32	47
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets		375	371
Total liabilities		0	0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets		81	91
Total liabilities		32	47
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets		0	0
Total liabilities		0	0
Other Current Assets | Fair Value, Measurements, Recurring [Member] | Exchange Traded Funds in Fixed Income securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, Fair Value Disclosure	[1]	14	14
Other Current Assets | Fair Value, Measurements, Recurring [Member] | Exchange Traded Funds in Fixed Income securities [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, Fair Value Disclosure	[1]	14	14
Other Current Assets | Fair Value, Measurements, Recurring [Member] | Exchange Traded Funds in Fixed Income securities [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, Fair Value Disclosure	[1]	0	0
Other Current Assets | Fair Value, Measurements, Recurring [Member] | Exchange Traded Funds in Fixed Income securities [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, Fair Value Disclosure	[1]	0	0
Other Current Assets | Fair Value, Measurements, Recurring [Member] | Foreign Currency Exchange Derivatives
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets		19	27
Other Current Assets | Fair Value, Measurements, Recurring [Member] | Foreign Currency Exchange Derivatives | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets		0	0
Other Current Assets | Fair Value, Measurements, Recurring [Member] | Foreign Currency Exchange Derivatives | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets		19	27
Other Current Assets | Fair Value, Measurements, Recurring [Member] | Foreign Currency Exchange Derivatives | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets		0	0
Other Current Assets | Fair Value, Measurements, Recurring [Member] | Commodity Derivatives
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets		2	9
Other Current Assets | Fair Value, Measurements, Recurring [Member] | Commodity Derivatives | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets		0	0
Other Current Assets | Fair Value, Measurements, Recurring [Member] | Commodity Derivatives | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets		2	9
Other Current Assets | Fair Value, Measurements, Recurring [Member] | Commodity Derivatives | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets		0	0
Other Noncurrent Assets | Fair Value, Measurements, Recurring [Member] | Available-for-sale Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, Fair Value Disclosure		4	10
Other Noncurrent Assets | Fair Value, Measurements, Recurring [Member] | Available-for-sale Securities [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, Fair Value Disclosure		4	10
Other Noncurrent Assets | Fair Value, Measurements, Recurring [Member] | Available-for-sale Securities [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, Fair Value Disclosure		0	0
Other Noncurrent Assets | Fair Value, Measurements, Recurring [Member] | Available-for-sale Securities [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, Fair Value Disclosure		0	0
Other Noncurrent Assets | Fair Value, Measurements, Recurring [Member] | Deferred compensation plan assets [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, Fair Value Disclosure		97	92
Other Noncurrent Assets | Fair Value, Measurements, Recurring [Member] | Deferred compensation plan assets [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, Fair Value Disclosure		97	92
Other Noncurrent Assets | Fair Value, Measurements, Recurring [Member] | Deferred compensation plan assets [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, Fair Value Disclosure		0	0
Other Noncurrent Assets | Fair Value, Measurements, Recurring [Member] | Deferred compensation plan assets [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, Fair Value Disclosure		0	0
Other Noncurrent Assets | Fair Value, Measurements, Recurring [Member] | Exchange Traded Funds in Fixed Income securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, Fair Value Disclosure	[1]	148	155
Other Noncurrent Assets | Fair Value, Measurements, Recurring [Member] | Exchange Traded Funds in Fixed Income securities [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, Fair Value Disclosure	[1]	148	155
Other Noncurrent Assets | Fair Value, Measurements, Recurring [Member] | Exchange Traded Funds in Fixed Income securities [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, Fair Value Disclosure	[1]	0	0
Other Noncurrent Assets | Fair Value, Measurements, Recurring [Member] | Exchange Traded Funds in Fixed Income securities [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, Fair Value Disclosure	[1]	0	0
Other Noncurrent Assets | Fair Value, Measurements, Recurring [Member] | Exchange traded funds in equity securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, Fair Value Disclosure	[1]	112	100
Other Noncurrent Assets | Fair Value, Measurements, Recurring [Member] | Exchange traded funds in equity securities [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, Fair Value Disclosure	[1]	112	100
Other Noncurrent Assets | Fair Value, Measurements, Recurring [Member] | Exchange traded funds in equity securities [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, Fair Value Disclosure	[1]	0	0
Other Noncurrent Assets | Fair Value, Measurements, Recurring [Member] | Exchange traded funds in equity securities [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, Fair Value Disclosure	[1]	0	0
Other Noncurrent Assets | Fair Value, Measurements, Recurring [Member] | Equity swap
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, Fair Value Disclosure		60	55
Other Noncurrent Assets | Fair Value, Measurements, Recurring [Member] | Equity swap | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, Fair Value Disclosure			0
Other Noncurrent Assets | Fair Value, Measurements, Recurring [Member] | Equity swap | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, Fair Value Disclosure		60	55
Other Noncurrent Assets | Fair Value, Measurements, Recurring [Member] | Equity swap | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, Fair Value Disclosure		0	0
Other Current Liabilities | Commodity Derivatives
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liabilities, Fair Value Disclosure, Recurring			1
Other Current Liabilities | Commodity Derivatives | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liabilities, Fair Value Disclosure, Recurring			0
Other Current Liabilities | Commodity Derivatives | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liabilities, Fair Value Disclosure, Recurring			1
Other Current Liabilities | Commodity Derivatives | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liabilities, Fair Value Disclosure, Recurring			0
Other Current Liabilities | Fair Value, Measurements, Recurring [Member] | Foreign Currency Exchange Derivatives
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities		29	46
Other Current Liabilities | Fair Value, Measurements, Recurring [Member] | Foreign Currency Exchange Derivatives | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities		0	0
Other Current Liabilities | Fair Value, Measurements, Recurring [Member] | Foreign Currency Exchange Derivatives | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities		29	46
Other Current Liabilities | Fair Value, Measurements, Recurring [Member] | Foreign Currency Exchange Derivatives | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities		0	$ 0
Other Current Liabilities | Fair Value, Measurements, Recurring [Member] | Commodity Derivatives
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities		3
Other Current Liabilities | Fair Value, Measurements, Recurring [Member] | Commodity Derivatives | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities		0
Other Current Liabilities | Fair Value, Measurements, Recurring [Member] | Commodity Derivatives | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities		3
Other Current Liabilities | Fair Value, Measurements, Recurring [Member] | Commodity Derivatives | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities		$ 0
[1]	1 Classified as restricted investments for payment of asbestos liabilities. See Note 20, "Commitments and Contingencies," of the notes to consolidated financial statements for further details.

Fair Value Measurements - Addit

Fair Value Measurements - Additional Information (Detail) $ in Millions, € in Billions, ¥ in Billions	9 Months Ended	12 Months Ended
	Jun. 30, 2018USD ($)	Sep. 30, 2017USD ($)	Jun. 30, 2018EUR (€)	Jun. 30, 2018JPY (¥)	Sep. 30, 2017EUR (€)	Sep. 30, 2017JPY (¥)
Derivative [Line Items]
Unrealized gains on marketable common stock	$ 20	$ 10
Unrealized losses on marketable common stock	18	6
Proceeds from Sale and Maturity of Marketable Securities	3
Marketable Securities, Realized Gain (Loss)	2
Fair value of long term debt	10,400	12,700
Fair Value, Inputs, Level 1 [Member]
Derivative [Line Items]
Fair value of long term debt	8,700	8,600
Fair Value, Inputs, Level 2 [Member]
Derivative [Line Items]
Fair value of long term debt	$ 1,700	$ 4,100
Foreign Currency Denominated Debt [Member]
Derivative [Line Items]
Notional amount | ¥				¥ 35		¥ 35
Foreign Currency Denominated Debt [Member] | One billion euro net investment hedge [Member]
Derivative [Line Items]
Notional amount | €			€ 1		€ 1

Impairment of Long-Lived Asse81

Impairment of Long-Lived Assets (Details) - USD ($) $ in Millions	3 Months Ended				9 Months Ended
	Dec. 31, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Jun. 30, 2018	Jun. 30, 2017
Impairment of Long Lived Assets [Line Items]
Asset Impairment Charges					$ 30	$ 70
2018 Restructuring Plan
Impairment of Long Lived Assets [Line Items]
Asset Impairment Charges	$ 30
2018 Restructuring Plan | Global Products
Impairment of Long Lived Assets [Line Items]
Asset Impairment Charges	23
2018 Restructuring Plan | Corporate Segment
Impairment of Long Lived Assets [Line Items]
Asset Impairment Charges	5
2018 Restructuring Plan | Power Solutions
Impairment of Long Lived Assets [Line Items]
Asset Impairment Charges	$ 2
2017 Restructuring Plan
Impairment of Long Lived Assets [Line Items]
Asset Impairment Charges		$ 31	$ 23	$ 15		69
2017 Restructuring Plan | Global Products
Impairment of Long Lived Assets [Line Items]
Asset Impairment Charges						20
2017 Restructuring Plan | Corporate Segment
Impairment of Long Lived Assets [Line Items]
Asset Impairment Charges						17
2017 Restructuring Plan | Power Solutions
Impairment of Long Lived Assets [Line Items]
Asset Impairment Charges						4
2017 Restructuring Plan | Building Solutions North America
Impairment of Long Lived Assets [Line Items]
Asset Impairment Charges						$ 28

Segment Information - Additiona

Segment Information - Additional Information (Detail)	3 Months Ended	9 Months Ended
	Sep. 30, 2017Segment	Jun. 30, 2018SegmentBusiness	Jun. 30, 2017Segment
Segment Reporting Information [Line Items]
Number of primary businesses | Business		2
Number of reportable segments		5
Building Technologies & Solutions
Segment Reporting Information [Line Items]
Number of reportable segments	4		5

Segment Information - Financial

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

Guarantees - Additional Informa

Guarantees - Additional Information (Detail) - USD ($) $ in Millions	9 Months Ended
	Jun. 30, 2018	Sep. 30, 2017	Sep. 30, 2016
Guarantor Obligations [Line Items]
Post sale contingent tax indemnification liabilities	$ 276	$ 290	$ 290
Maximum length, in years, of a product warranty for it to be recorded in other current liabilities	1 year
Minimum length, in years, of a product warranty for it to be recorded in other noncurrent liabilities	1 year
Business Divestitures, Not Specific [Member]
Guarantor Obligations [Line Items]
Post sale contingent tax indemnification liabilities	$ 235

Product Warranties - Changes in

Product Warranties - Changes in Carrying Amount of Product Warranty liability (Detail) - USD ($) $ in Millions	9 Months Ended
	Jun. 30, 2018	Jun. 30, 2017
Movement in Standard Product Warranty Accrual [Roll Forward]
Balance at beginning of period	$ 409	$ 374
Accruals for warranties issued during the period	225	221
Accruals from acquisition and divestitures	1	2
Accruals related to pre-existing warranties	(24)	(5)
Settlements made (in cash or in kind) during the period	(212)	(199)
Currency translation	0	(1)
Balance at end of period	$ 399	$ 392

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Detail)	3 Months Ended	9 Months Ended	12 Months Ended
	Sep. 30, 2017USD ($)	Jun. 30, 2018USD ($)	Sep. 30, 2017USD ($)
Loss Contingencies [Line Items]
Estimated asbestos related net liability on a discounted basis	$ 181,000,000	$ 180,000,000	$ 181,000,000
Reserves for environmental liabilities	51,000,000	43,000,000	51,000,000
Conditional asset retirement obligations	61,000,000	48,000,000	61,000,000
Accrued Environmental Loss Contingencies, Current	10,000,000	14,000,000	10,000,000
Accrued Environmental Loss Contingencies, Noncurrent	41,000,000	29,000,000	41,000,000
Liability for Asbestos and Environmental Claims, Gross	573,000,000	557,000,000	573,000,000
Restricted Cash and Investments	392,000,000	377,000,000	392,000,000
Restricted Cash and Cash Equivalents	31,000,000	19,000,000	31,000,000
Insurance Recoveries		93,000,000	101,000,000
Insurable liabilities	445,000,000	444,000,000	445,000,000
Insurance Settlements Receivable, Current	31,000,000	6,000,000	31,000,000
Insurance Settlements Receivable	46,000,000	21,000,000	46,000,000
Insurance Settlements Receivable, Noncurrent	15,000,000	$ 15,000,000	15,000,000
Arbitration award to plaintiff	$ 50,000,000
Accrued interest while arbitration award remains outstanding	9.56%
Class actions lawsuits against the Company		16
Asbestos Issue [Member]
Loss Contingencies [Line Items]
Restricted Cash and Cash Equivalents	$ 22,000,000	$ 10,000,000	22,000,000
Restricted Investments	269,000,000	274,000,000	269,000,000
Selling, General And Administrative
Loss Contingencies [Line Items]
Arbitration award to plaintiff	50,000,000
Accrued Compensation and Benefits [Member]
Loss Contingencies [Line Items]
Insurable liabilities	22,000,000	25,000,000	22,000,000
Other Current Assets
Loss Contingencies [Line Items]
Restricted Cash and Investments	53,000,000	41,000,000	53,000,000
Other Noncurrent Assets
Loss Contingencies [Line Items]
Restricted Cash and Investments	339,000,000	336,000,000	339,000,000
Other Noncurrent Liabilities [Member]
Loss Contingencies [Line Items]
Liability for Asbestos and Environmental Claims, Gross	525,000,000	503,000,000	525,000,000
Insurable liabilities	301,000,000	339,000,000	301,000,000
Other Current Liabilities
Loss Contingencies [Line Items]
Liability for Asbestos and Environmental Claims, Gross	48,000,000	54,000,000	48,000,000
Insurable liabilities	$ 122,000,000	$ 80,000,000	$ 122,000,000

Related Party Transactions (Det

Related Party Transactions (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Sep. 30, 2017
Related Party Transaction [Line Items]
Receivable from related parties	$ 109		$ 109		$ 108
Payable to related parties	51		51		$ 50
Revenue from related parties	256	$ 251	720	$ 705
Purchases from related parties	$ 45	$ 64	$ 137	$ 165