Name:	osk_DebtInstrumentCovenantTermsInterestCoverageRatio
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The denominator of the minimum interest coverage ratio (i.e., the Company's consolidated EBITDA to the Company's consolidated cash interest expenses) required to be maintained by the entity as of the last day of any fiscal quarter.

No definition available.

Name:	osk_DebtInstrumentCovenantTermsInterestCoverageRatioMinimumDenominator
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Debt Instrument, Covenant Terms, Senior Secured Leverage Ratio

No definition available.

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Debt Instrument, Covenant Terms, Senior Secured, Leverage Ratio for Intermediate Period Maximum Denominator

No definition available.

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Debt Instrument, Covenant Terms, Senior Secured, Leverage Ratio for Intermediate Period Maximum Without Collateral, Denominator

No definition available.

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Debt Instrument, Covenant Terms, Senior Secured Leverage Ratio without collateral

No definition available.

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Debt Instrument, Dividends and Other Distributions Restrictions, Percentage of Aggregate Net Proceeds Received

No definition available.

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Debt Instrument, Dividends and Other Distributions Restrictions, Percentage of Consolidated Net Deficit Deducted

No definition available.

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Represents the percentage of consolidated net income of the entity and its consolidated subsidiaries for all fiscal quarters ending after the date the company entered into new credit agreement used to determine maximum dividends or other distributions paid during the fiscal year.

No definition available.

Name:	osk_DebtInstrumentDividendsAndOtherDistributionsRestrictionsPercentageOfConsolidatedNetIncomeConsidered
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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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The denominator of 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_DebtInstrumentLeverageRatioMaximumDenominator
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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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Data Type:	num:percentItemType
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Period Type:	duration

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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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

Amount of short-term debt and current maturity of long-term debt and capital lease obligations due within one year or the normal operating cycle, if longer.

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Data Type:	xbrli:monetaryItemType
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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

No definition available.

Name:	us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
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Data Type:	num:percentItemType
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Period Type:	duration

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Period Type:	instant

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/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=73719730&loc=d3e13433-108611

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Period Type:	instant

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

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Data Type:	num:percentItemType
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Amount of the required periodic payments applied to principal.

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

Amount of payment greater than the preceding installment payments to be paid at final maturity date of debt.

No definition available.

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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

Weighted average interest rate of debt outstanding.

No definition available.

Name:	us-gaap_DebtWeightedAverageInterestRate
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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28555-108399

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-Paragraph 1
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- References

No definition available.

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

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

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

Name:	us-gaap_LineOfCredit
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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.

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

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

Name:	us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity
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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
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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/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
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-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Name:	us-gaap_LongTermDebt
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Period Type:	instant

- References

No definition available.

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

Name:	us-gaap_LongTermDebtCurrent
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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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

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

No definition available.

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

Name:	us-gaap_DebtInstrumentAxis=osk_SeniorSecuredCreditAgreementMember
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Name:	us-gaap_RangeAxis=us-gaap_MinimumMember
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Name:	us-gaap_RangeAxis=us-gaap_MaximumMember
Namespace Prefix:
Data Type:	na
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Name:	us-gaap_DebtInstrumentAxis=osk_SeniorSecuredTermLoanMember
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Data Type:	na
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Name:	us-gaap_DebtInstrumentAxis=us-gaap_RevolvingCreditFacilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

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Namespace Prefix:
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Data Type:	na
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