Schedule I - Condensed Financial Information of U-Haul Holding Company (Statements of Comprehensive Income) (Details) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Mar. 31, 2022
Net Income (Loss)	$ 628,707	$ 924,472	$ 1,124,362
Total comprehensive income (loss) (net of tax)	691,114	640,755	1,080,137
U-Haul Holding Company [Member]
Net Income (Loss)	628,707	924,472	1,124,362
Other comprehensive income (loss)	62,183	288,339	41,133
Total comprehensive income (loss) (net of tax)	$ 690,890	$ 636,133	$ 1,083,229