Goodwill and Intangible Assets (Reconciliation of Goodwill) (Details) $ in Millions	6 Months Ended
Jan. 31, 2021 USD ($)
Goodwill
Beginning balance	$ 316.8
Goodwill acquired	0.0
Currency translation	5.3
Ending balance	322.1
Engine Products
Goodwill
Beginning balance	84.8
Goodwill acquired	0.0
Currency translation	0.1
Ending balance	84.9
Industrial Products
Goodwill
Beginning balance	232.0
Goodwill acquired	0.0
Currency translation	5.2
Ending balance	$ 237.2

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://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(10)(1))
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

Reference 2: 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=120320667&loc=SL49117168-202975

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-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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-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
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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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-SubTopic 20
-Section 50
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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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