Derivatives (Narratives) (Details) - USD ($) $ in Millions	6 Months Ended
Sep. 30, 2022	Sep. 30, 2021
Interest Rate Derivatives [Abstract]
Notional amount of operating lease	$ 6.4	$ 0.1
Reclassify net losses on interest rate contracts from AOCI to earnings over the next twelve months	0.4	$ 105.0
Amounts reclassified from AOCI to interest expense	$ 0.4

Aggregate notional amount on operating lease derivatives, which relates to the currency amount specified on operating lease derivatives.

No definition available.

+ Details

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Namespace Prefix:	uhal_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The estimated value of gains (losses), net anticipated to be transferred in the future from accumulated other comprehensive income into earnings.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 30
-Section 50
-Paragraph 6
-URI https://asc.fasb.org/extlink&oid=121549185&loc=d3e80845-113994

+ Details

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- Definition

The amount of net gains or losses on interest rate cash flow hedges reclassified during the period to earnings from accumulated other comprehensive income upon the hedged transaction affecting earnings.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (c)
-URI https://asc.fasb.org/extlink&oid=125515794&loc=SL5624171-113959

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- References

No definition available.

+ Details

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