Schedule I - Condensed Financial Information of AMERCO (Narratives) (Details) - USD ($) $ in Thousands	12 Months Ended
Mar. 31, 2022	Mar. 31, 2021	Mar. 31, 2020
Income Taxes Paid, Net [Abstract]
Income taxes paid (net of income tax refunds)	$ (4,548)	$ 29,044	$ 6,859

The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income, net of any cash received during the current period as refunds for the overpayment of taxes.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=123431023&loc=d3e4297-108586

Name:	us-gaap_IncomeTaxesPaidNet
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration