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Fleet loan provision specified LIBOR plus applicable margin. This is the lower of the two applicable margin rates at the time of the loan agreement.

No definition available.

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

No definition available.

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Historic applicable margin. This is the lower of the rate range.

No definition available.

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The debt agreement amount at the beginning of this contract. It is no longer valid because of a subsequent amendment in the terms of this loan.

No definition available.

Name:	uhal_DebtInstrumentOriginalFaceAmount
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Fees on early extinguishment of debt

No definition available.

Name:	uhal_FeesOnEarlyExtinguishmentOfDebt
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We include two different LIBOR rates for these loans in our documentation.

No definition available.

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

No definition available.

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Sum of the carrying values as of the balance sheet date of all debt, including all short-term borrowings, long-term debt, and 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 210.7-03.16)

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.13,16)

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The effective interest rate at the end of the reporting period.

No definition available.

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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/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399

Reference 2: 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(a)(1))

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

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(a)(1))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Name:	us-gaap_DebtInstrumentInterestRateStatedPercentageAbstract
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Maximum contractual interest rate for funds borrowed, under the debt agreement.

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Data Type:	num:percentItemType
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Minimum contractual interest rate for funds borrowed, under the debt agreement.

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(a)(2))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Name:	us-gaap_DebtInstrumentInterestRateStatedPercentageRateRangeMinimum
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Data Type:	num:percentItemType
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Date the debt instrument was issued, in CCYY-MM-DD format.

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(a))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Name:	us-gaap_DebtInstrumentIssuanceDate1
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Balance Type:	na
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/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(2))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Latest date the outstanding debt instruments are required to be repaid, in CCYY-MM-DD format.

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(a)(2))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Earliest date the outstanding debt instruments are required to be repaid, in CCYY-MM-DD format.

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(a)(2))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Date the derivative contract matures, in CCYY-MM-DD format.

No definition available.

Name:	us-gaap_DerivativeMaturityDates
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Data Type:	xbrli:dateItemType
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A general description of the lessee's leasing arrangements including, but not limited to, the following: a) the basis on which contingent rental payments are determined; (b) the existence and terms of renewal or purchase options and escalation clauses; (c) restrictions imposed by lease agreements, such as those concerning dividends, additional debt, and further leasing.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6452660&loc=d3e36991-112694

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 440

-SubTopic 10

-Section 25

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6394851&loc=SL2265659-115463

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 10

-Section 15

-Paragraph 17

-URI http://asc.fasb.org/extlink&oid=51672649&loc=d3e32400-112679

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Gross amount of debt extinguished.

No definition available.

Name:	us-gaap_ExtinguishmentOfDebtAmount
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

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://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.19(b),22(b))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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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://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.19(b),22(b))

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

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 210.5-02.19(b),22(b))

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Balance Type:	credit
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Name:	us-gaap_LongTermDebtAbstract
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Name:	us-gaap_LongTermDebtOtherDisclosuresAbstract
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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
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Data Type:	num:percentItemType
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Stated maturity date of the mortgage loan receivable on real estate, in CCYY-MM-DD format.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 205

-SubTopic 10

-Section S99

-Paragraph 6

-Subparagraph (SX 210.5-04.(c) Schedule IV)

-URI http://asc.fasb.org/extlink&oid=27047687&loc=d3e5864-122674

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 948

-SubTopic 310

-Section S99

-Paragraph 1

-Subparagraph (SX 210.12-29)

-URI http://asc.fasb.org/extlink&oid=6589523&loc=d3e617274-123014

Name:	us-gaap_MortgageLoanOnRealEstateFinalMaturityDate
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The carrying amount as of the balance sheet date for the aggregate of other miscellaneous borrowings owed by the reporting entity.

Name:	us-gaap_OtherBorrowings
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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The net amount of capitalized assets classified as property, plant and equipment not otherwise defined in the taxonomy.

No definition available.

Name:	us-gaap_PropertyPlantAndEquipmentOtherNet
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Carrying value as of the balance sheet date, including the current and noncurrent portions, of collateralized debt obligations (with maturities initially due after one year or beyond the operating cycle, if longer). Such obligations include mortgage loans, chattel loans, and any other borrowings secured by assets of the borrower.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.16)

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 20, 22

-Article 5

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.16)

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.8)

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

Name:	us-gaap_WriteOffOfDeferredDebtIssuanceCost
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Name:	us-gaap_StatementBusinessSegmentsAxis=uhal_AmercoBusinessSegmentMember
Namespace Prefix:
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Name:	us-gaap_StatementBusinessSegmentsAxis=uhal_AmercoRealEstateCompanyMember
Namespace Prefix:
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Name:	us-gaap_StatementBusinessSegmentsAxis=uhal_AmercoRealEstateSubsidiariesAndUhaulCompanyOfFloridaMember
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Name:	us-gaap_StatementBusinessSegmentsAxis=uhal_AmercoRealEstateUhaulCompanyFloridaMember
Namespace Prefix:
Data Type:	na
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Name:	us-gaap_StatementBusinessSegmentsAxis=uhal_AmercoUsBankNationalAssociationTrusteeMember
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Name:	us-gaap_StatementBusinessSegmentsAxis=uhal_UhaulIntlAndSubsidiariesMember
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