Revenue Recognition - Schedule of Changes in Warranty Liability and Unearned Extended Warranty Premiums (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Disaggregation Of Revenue [Abstract]
Balance at beginning of period	$ 66.9	$ 63.0
Deferred revenue for new service warranties	7.2	6.5
Amortization of deferred revenue	(4.8)	(6.4)
Foreign currency translation	(0.2)	(0.2)
Balance at end of period	$ 69.1	$ 62.9

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 http://asc.fasb.org/extlink&oid=123368208&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 http://asc.fasb.org/extlink&oid=123368208&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 http://asc.fasb.org/extlink&oid=123368208&loc=d3e12565-110249

+ Details

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