Name:	osk_DebtInstrumentCovenantTermsInterestCoverageRatio
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The maximum leverage ratio (i.e., the ratio of the Company's consolidated indebtedness to its consolidated net income) required to be maintained by the entity as of the last day of any fiscal quarter.

No definition available.

Name:	osk_DebtInstrumentLeverageRatio
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Data Type:	xbrli:pureItemType
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Period Type:	instant

Debt Instrument month and year.

No definition available.

Name:	osk_DebtInstrumentMonthAndYear
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Period Type:	duration

Debt instrument periodic payment terms balloon payment paid.

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Debt instrument redemption discount.

No definition available.

Name:	osk_DebtInstrumentRedemptionDiscount
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Balance Type:	debit
Period Type:	duration

Represents the minimum fees for the letter of credit facility, expressed as a percent of the maximum amount available to be drawn against the letter of credit issued and outstanding under the credit facility.

No definition available.

Name:	osk_LetterOfCreditFeesPercentageOnAvailableBorrowingCapacityLowEndOfRange
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Represents the maximum fees for the letter of credit facility, expressed as a percent of the maximum amount available to be drawn against each letter of credit issued and outstanding under the credit facility.

No definition available.

Name:	osk_LetterOfCreditRatePercentageOnAvailableBorrowingCapacityHighEndOfRange
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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

No definition available.

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Data Type:	num:percentItemType
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Period Type:	duration

Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=121572278&loc=d3e13433-108611

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Contractual interest rate for funds borrowed, under the debt agreement.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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-Section S99
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-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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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.

No definition available.

Name:	us-gaap_DebtInstrumentLineItems
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Data Type:	xbrli:stringItemType
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Period Type:	duration

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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Data Type:	xbrli:dateItemType
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Period Type:	duration

Amount of the required periodic payments applied to principal.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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Amount of payment greater than the preceding installment payments to be paid at final maturity date of debt.

No definition available.

Name:	us-gaap_DebtInstrumentPeriodicPaymentTermsBalloonPaymentToBePaid
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- References

No definition available.

Name:	us-gaap_DebtInstrumentsAbstract
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Data Type:	xbrli:stringItemType
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Represents the charge against earnings during the period for commitment fees and debt issuance expenses.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
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-Paragraph 2
-Subparagraph (SX 210.5-03.8)
-URI http://asc.fasb.org/extlink&oid=120395209&loc=SL114868664-224227

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Weighted average interest rate of debt outstanding.

No definition available.

Name:	us-gaap_DebtWeightedAverageInterestRate
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

No definition available.

Name:	us-gaap_LettersOfCreditOutstandingAmount
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Name:	us-gaap_LineOfCreditFacilityCurrentBorrowingCapacity
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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Name:	us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

No definition available.

Name:	us-gaap_LineOfCreditFacilityUnusedCapacityCommitmentFeePercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)(3)
-URI http://asc.fasb.org/extlink&oid=120520924&loc=SL6031897-161870

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-Name Accounting Standards Codification
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-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16))
-URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910

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-Name Accounting Standards Codification
-Topic 942
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-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

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-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
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Name:	us-gaap_LongTermDebt
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- References

No definition available.

Name:	us-gaap_LongTermDebtAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
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-Section 45
-Paragraph 14
-Subparagraph (b)
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Name:	us-gaap_ProceedsFromIssuanceOfDebt
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
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Name:	us-gaap_RepaymentsOfDebt
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- References

No definition available.

Name:	us-gaap_ShortTermBorrowingsAbstract
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The portion of the carrying amount of short-term borrowings outstanding as of the balance sheet date, which accrues interest at a rate subject to change from time to time.

No definition available.

Name:	us-gaap_ShortTermDebtPercentageBearingVariableInterestRate
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

For the form of debt having an initial term of less than one year or less than the normal operating cycle, if longer, the maximum amount borrowed at any time during the period.

No definition available.

Name:	us-gaap_ShorttermDebtMaximumAmountOutstandingDuringPeriod
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

Write-off of amounts previously capitalized as debt issuance cost in an extinguishment of debt.

Name:	us-gaap_WriteOffOfDeferredDebtIssuanceCost
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Name:	us-gaap_LineOfCreditFacilityAxis=osk_UncommittedLineOfCreditMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_CreditFacilityAxis=us-gaap_RevolvingCreditFacilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_CreditFacilityAxis=us-gaap_LetterOfCreditMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_DebtInstrumentAxis=osk_SeniorTermLoanMemberMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_DebtInstrumentAxis=osk_SeniorCreditAgreementMemberMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	srt_RangeAxis=srt_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	srt_RangeAxis=srt_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_DebtInstrumentAxis=osk_SeniorCreditAgreementDollarDenominatedLoansMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_VariableRateAxis=osk_DebtInstrumentVariableRateBaseFederalMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	us-gaap_VariableRateAxis=osk_DebtInstrumentVariableRateBaseLIBORMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	us-gaap_DebtInstrumentAxis=osk_A5375SeniorNotesDueMarch2025Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_DebtInstrumentAxis=osk_A4600SeniorNotesDueMay2028Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_DebtInstrumentAxis=osk_ThreePointOneZeroZeroSeniorNotesDueMarch2030Member
Namespace Prefix:
Data Type:	na
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