Goodwill and Other Intangible Assets (Reconciliation of Goodwill) (Details) $ in Millions	9 Months Ended
Apr. 30, 2019 USD ($)
Goodwill [Roll Forward]
Beginning balance	$ 238.4
Goodwill acquired	73.6
Foreign exchange translation	(3.2)
Ending balance	308.8
Engine Products
Goodwill [Roll Forward]
Beginning balance	84.9
Goodwill acquired	0.0
Foreign exchange translation	(0.4)
Ending balance	84.5
Industrial Products
Goodwill [Roll Forward]
Beginning balance	153.5
Goodwill acquired	73.6
Foreign exchange translation	(2.8)
Ending balance	$ 224.3

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
-Topic 350
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-Section 45
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-URI http://asc.fasb.org/extlink&oid=99380562&loc=d3e13770-109266

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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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