Derivative hedge market value as of balance sheet date.

No definition available.

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- Definition

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

+ References

No definition available.

+ Details

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

- References

No definition available.

+ Details

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Period Type:	duration

- 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 http://asc.fasb.org/extlink&oid=121549185&loc=d3e80845-113994

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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- Definition

Nominal or face amount used to calculate payment on derivative.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=125515794&loc=SL5580258-113959

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=125515794&loc=SL5579245-113959

+ Details

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Period Type:	instant

- Definition

Amount after tax and reclassification adjustments, of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 10A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=124509347&loc=SL7669646-108580

+ Details

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Balance Type:	credit
Period Type:	duration

Derivatives (Narratives) (Details) - USD ($) $ in Thousands	12 Months Ended
Derivatives (Narratives) (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2021	Dec. 31, 2020
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Other Comprehensive Income Loss Derivatives Qualifying As Hedges Net Of Tax	$ 457	$ (429)	$ (6,301)
Notional amount of operating lease				$ 7,500	$ 6,600
Reclassify net losses on interest rate contracts from AOCI to earnings over the next twelve months	3,900
Derivative hedge market value	$ 1,200
Derivative Notional Amount				$ 416,700	$ 282,700