Revenue Recognition - Schedule of Changes in Warranty Liability and Unearned Extended Warranty Premiums (Details) - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2022	Sep. 30, 2021
Disaggregation of Revenue [Abstract]
Balance at beginning of period	$ 66.9	$ 63.0
Deferred revenue for new service warranties	21.6	21.2
Amortization of deferred revenue	(16.1)	(18.2)
Foreign currency translation	(0.9)	(0.2)
Balance at end of period	$ 71.5	$ 65.8

Product warranty amortization.

No definition available.

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Namespace Prefix:	osk_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- References

No definition available.

+ Details

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- Definition

Amount as of the balance sheet date of the aggregate extended product warranty liability. Does not include the ending balance for the standard product warranty liability.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (c)(1),(c)(5)
-URI https://asc.fasb.org/extlink&oid=126907703&loc=d3e12565-110249

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Amount of foreign currency translation gain (loss) which decreases (increases) the extended product warranty accrual. Excludes standard product warranties.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (c)
-URI https://asc.fasb.org/extlink&oid=126907703&loc=d3e12565-110249

+ Details

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- Definition

Amount of increase in the extended product warranty accrual from warranties issued. Excludes standard product warranties.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (c)(3)
-URI https://asc.fasb.org/extlink&oid=126907703&loc=d3e12565-110249

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