Name:	uhal_ApplicableMarginPerLoanAgreementMaximumRate
Namespace Prefix:	uhal_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

Historic applicable margins. This is the higher of the rate range.

No definition available.

Name:	uhal_ApplicableMarginsHighRate
Namespace Prefix:	uhal_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

The DebtInstrumentMaturityDate could have worked for this element, but it must include the format Month-Date-Year. Will use this US-GAAP Element in the next few schedules, when possible, where we break down the various items that make up the Borrowing's narrative.

No definition available.

Name:	uhal_MaturityYear
Namespace Prefix:	uhal_
Data Type:	xbrli:gYearItemType
Balance Type:	na
Period Type:	duration

Weighted average remaining lease term for finance lease.

No definition available.

Name:	uhal_RemainingLeaseTermFinanceLeaseWeightedAverage
Namespace Prefix:	uhal_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

The amount of corporate (parent company) debt held by our insurance subsidiaries.

No definition available.

Name:	uhal_SubsidiariesShareOfDebtPurchasedFromParent
Namespace Prefix:	uhal_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Equity securities categorized neither as held-to-maturity nor trading which are intended be sold more than one year from the balance sheet date or operating cycle, if longer.

No definition available.

Name:	us-gaap_AvailableForSaleSecuritiesEquitySecuritiesNoncurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Amount of short-term and long-term debt and lease obligation.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
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Name:	us-gaap_DebtAndCapitalLeaseObligations
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
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-Section 50
-Paragraph 6
-Subparagraph (a)
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-Name Accounting Standards Codification
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Name:	us-gaap_DebtInstrumentInterestRateEffectivePercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

No definition available.

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

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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Name:	us-gaap_DebtInstrumentInterestRateStatedPercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

No definition available.

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

Amount of restricted investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 50
-Paragraph 1A
-Subparagraph (b)(1)(i)
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Name:	us-gaap_DebtSecuritiesAvailableForSaleRestricted
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

No definition available.

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

Amount of advances from the Federal Home Loan Bank (FHLB).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 45
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Name:	us-gaap_FederalHomeLoanBankAdvancesBranchOfFHLBBankAmountOfAdvancesByBranch
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Discloses the single interest rate [if] applicable to the advances from the Federal Home Loan Bank, by branch, as of the Balance Sheet date.

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Name:	us-gaap_FederalHomeLoanBankAdvancesBranchOfFHLBBankInterestRate
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
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
-Publisher FASB
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-Subparagraph (SX 210.5-02.19(b),22(b))
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Name:	us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity
Namespace Prefix:	us-gaap_
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).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-Paragraph 1
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Name:	us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

No definition available.

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

No definition available.

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

The interest rate applicable to the portion of the carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a rate subject to change from time to time.

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

The portion of the carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a set, unchanging rate.

No definition available.

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

The percentage charged for managing real estate properties.

No definition available.

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

Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_MortgagesMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	srt_RangeAxis=srt_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	srt_RangeAxis=srt_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_LineOfCreditMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	srt_ConsolidatedEntitiesAxis=srt_ParentCompanyMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

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

Name:	us-gaap_LongtermDebtTypeAxis=uhal_FleetLoansSecuritizationMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_CapitalLeaseObligationsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_StatementBusinessSegmentsAxis=uhal_AmercoRealEstateSubsidiariesAndUhaulCompanyOfFloridaMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_StatementBusinessSegmentsAxis=uhal_VariousSubsidiariesOfAmercoRealEstateAndUhaulIntlMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_SeniorLoansMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_StatementBusinessSegmentsAxis=uhal_UhaulIntlAndSubsidiariesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_MediumTermNotesMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	us-gaap_LongtermDebtTypeAxis=uhal_RentalTruckRevolversMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	us-gaap_StatementBusinessSegmentsAxis=uhal_AmercoUsBankNationalAssociationTrusteeMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_CollateralizedDebtObligationsMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	us-gaap_StatementBusinessSegmentsAxis=uhal_LifeInsuranceMember
Namespace Prefix:
Data Type:	na
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