Acquisitions - Narrative (Details) - USD ($)			1 Months Ended		7 Months Ended	12 Months Ended
	Aug. 31, 2021	Oct. 01, 2019	Aug. 31, 2021	Jan. 31, 2020	Apr. 30, 2020	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Business Acquisition [Line Items]
Goodwill						$ 3,524,000,000	$ 3,625,900,000
Cash, net of cash acquired		$ 247,000,000.0
Finite-lived intangible assets acquired, discount rate		11.00%
Noncontrolling interest portion of Rockwell Automation's contributed business		$ 25,800,000
Software & Control
Business Acquisition [Line Items]
Goodwill						2,398,700,000	2,447,500,000
Fiscal 2022 Acquisitions
Business Acquisition [Line Items]
Pro forma revenue						7,800,000,000	7,100,000,000
Fiscal 2021 Acquisitions
Business Acquisition [Line Items]
Sales							27,900,000
Pro forma revenue							$ 7,200,000,000	$ 6,500,000,000
Plex Systems
Business Acquisition [Line Items]
Acquired finite-lived intangible assets, weighted average useful life			12 years
Customer attrition rate	5.00%
Royalty rate	25.00%
Obsolescence factor phase out period	10 years
Goodwill	$ 1,730,000,000		$ 1,730,000,000
Plex Systems | Customer relationships
Business Acquisition [Line Items]
Finite-lived intangible assets acquired	276,400,000
Plex Systems | Patented Technology
Business Acquisition [Line Items]
Finite-lived intangible assets acquired	232,800,000
Plex Systems | Trade Names
Business Acquisition [Line Items]
Finite-lived intangible assets acquired	$ 22,200,000
Oylo And Fiix Inc.
Business Acquisition [Line Items]
Goodwill									$ 224,800,000
Oylo And Fiix Inc. | Customer Relationships, Technology, and Trade Names
Business Acquisition [Line Items]
Finite-lived intangible assets acquired						$ 69,600,000
Acquired finite-lived intangible assets, weighted average useful life						11 years
Oylo And Fiix Inc. | Lifecycle Services
Business Acquisition [Line Items]
Goodwill						$ 12,800,000
Oylo And Fiix Inc. | Software & Control
Business Acquisition [Line Items]
Goodwill						$ 212,000,000
Sensia
Business Acquisition [Line Items]
Goodwill		307,400,000
Pro forma revenue		$ 191,000,000
Business acquisition, percentage of voting interests acquired		53.00%
Cash, net of cash acquired		$ 247,000,000
Noncontrolling interest portion of Rockwell Automation's contributed business		$ 293,800,000
Sensia | Schlumberger
Business Acquisition [Line Items]
Business acquisition, percentage of voting interests acquired		47.00%
Sensia | Minimum
Business Acquisition [Line Items]
Customer attrition rate		7.50%
Sensia | Maximum
Business Acquisition [Line Items]
Customer attrition rate		25.00%
Sensia | Customer Relationships, Technology, and Trade Names
Business Acquisition [Line Items]
Finite-lived intangible assets acquired		$ 254,100,000
Acquired finite-lived intangible assets, weighted average useful life		11 years
Sensia | Technology and Trademarks | Minimum
Business Acquisition [Line Items]
Acquired finite-lived intangible assets, weighted average useful life		5 years
Sensia | Technology and Trademarks | Maximum
Business Acquisition [Line Items]
Acquired finite-lived intangible assets, weighted average useful life		15 years
Avnet
Business Acquisition [Line Items]
Number of years of experience				20 years
MESTECH, Avnet, ASEM, and Kalypso
Business Acquisition [Line Items]
Sales								$ 41,800,000
Business acquisition, goodwill, expected tax deductible amount					$ 69,000,000
Contingent consideration					25,800,000
MESTECH, Avnet, ASEM, and Kalypso | Customer Relationships, Technology, and Trade Names
Business Acquisition [Line Items]
Finite-lived intangible assets acquired					76,500,000
Sales					10
MESTECH, Avnet, ASEM, and Kalypso | Lifecycle Services
Business Acquisition [Line Items]
Goodwill					83,300,000
MESTECH, Avnet, ASEM, and Kalypso | Software & Control
Business Acquisition [Line Items]
Goodwill					$ 161,200,000