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

These agreements and notes with subsidiaries of SAC Holdings, 4 SAC, 5 SAC, Galaxy and Private Mini, Excluded Dealer Agreements commission expenses.

No definition available.

Name:	uhal_CommissionExpensesGeneratedFromDealerAgreementWithRelatedParty
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

We provide the largest aggregate amount of related party notes receivable that occurred during this reporting period. This can be compared to the related party notes receivable balance at the end of this period.

No definition available.

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Balance Type:	na
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One time interest payment received on loans and other debt instruments.

No definition available.

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- References

No definition available.

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The US-GAAP taxonomy only contains a single date for related party transactions. RelatedPartyTransaction Date. We disclose our earliest and latest maturities on the various outstanding notes only by the year.

No definition available.

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Data Type:	xbrli:gYearItemType
Balance Type:	na
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The amount of revenue received excluding any revenue generated from dealer commissions or expenses as part of the dealer contract between the Company and these related party entities.

No definition available.

Name:	uhal_RevenueExcludingDealerAgreementCommissionsAndExpenses
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

This provides just the cost and expense for SAC holdings.

No definition available.

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

Amount of revenue earned from products sold or services provided under the terms of a contract, including, but not limited to, government contracts and construction contracts, classified as other.

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 210.5-03.1)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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Base revenue, as contractually stipulated, for operating and managing another entity's business during the reporting period.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- References

No definition available.

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

For an unclassified balance sheet, amounts due from parties associated with the reporting entity as evidenced by a written promise to pay.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(k)(1))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 210
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-Subparagraph (SX 210.7-03.3)
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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-Paragraph 1
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Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=16382449

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

Interest received on loans and other debt instruments during the current period.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 25
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3536-108585

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

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

- References

No definition available.

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

Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=uhal_SacHoldingsMember
Namespace Prefix:
Data Type:	na
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Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=uhal_SacHoldingsMercuryFourSacFiveSacGalaxyAndPrivateMiniMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

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

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

Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=uhal_PrivateMiniMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_RangeAxis=us-gaap_MinimumMember
Namespace Prefix:
Data Type:	na
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