Consolidated Statements of Cash Flows - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Operating Activities of Continuing Operations
Net income from continuing operations attributable to Johnson Controls	$ 381	$ 327
Income from continuing operations attributable to noncontrolling interests	38	45
Income from continuing operations	419	372
Adjustments to reconcile net income from continuing operations to cash provided by operating activities:
Depreciation and amortization	224	207
Pension and postretirement benefit income	(82)	(46)
Pension and postretirement contributions	(41)	(17)
Equity in earnings of partially-owned affiliates, net of dividends received	(18)	(52)
Deferred income taxes	(32)	(59)
Equity-based compensation	29	22
Other - net	(28)	(47)
Changes in assets and liabilities, excluding acquisitions and divestitures:
Accounts receivable	(75)	224
Inventories	(376)	(98)
Other assets	(63)	(70)
Restructuring reserves	19	(34)
Accounts payable and accrued liabilities	333	91
Accrued income taxes	83	22
Cash provided by operating activities from continuing operations	392	515
Investing Activities of Continuing Operations
Capital expenditures	(135)	(91)
Sale of property, plant and equipment	7	34
Acquisition of businesses, net of cash acquired	(108)	0
Business divestitures, net of cash divested	16	11
Changes in long-term investments	2	9
Cash used by investing activities	(218)	(37)
Financing Activities of Continuing Operations
Increase (decrease) in short-term debt - net	394	(20)
Stock repurchases and retirements	(526)	(346)
Payment of cash dividends	(191)	(190)
Proceeds from the exercise of stock options	8	31
Employee equity-based compensation withholding taxes	(47)	(21)
Other - net	5	(1)
Cash used by financing activities from continuing operations	(357)	(547)
Discontinued Operations
Cash Used by Operating Activities, Discontinued Operations	(4)	(36)
Net Cash Used by Discontinued Operations	(4)	(36)
Effect of Exchange Rate on Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Including Disposal Group and Discontinued Operations	67	(11)
Decrease in Cash, Cash Equivalents and Restricted Cash	(120)	(116)
Cash, cash equivalents and restricted cash at beginning of period	1,342	1,960
Cash, cash equivalents and restricted cash at end of period	1,222	1,844
Less: Restricted Cash	15	5
Cash and cash equivalents at end of period	$ 1,207	$ 1,839