Rocky Flats Settlement (Details) - Rocky Flats - USD ($) $ in Thousands	1 Months Ended	12 Months Ended
Jan. 31, 2017	Sep. 30, 2018	Sep. 30, 2016
Loss Contingencies [Line Items]
Settlement amount, in aggregate		$ 375,000
Settlement amount, total Rockwell obligation		$ 243,750
Settlement amount, payments made to plaintiff class escrow fund	$ 243,750		$ 1,250

Amount of judgment or settlement awarded to (against) the entity and other parties, in the aggregate, in respect of litigation.

No definition available.

+ Details

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Namespace Prefix:	rok_
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- Definition

Amount awarded to other party in judgment or settlement of litigation.

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

The amount of cash paid for the settlement of litigation or for other legal issues during the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 25
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3536-108585

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