Schedule I - Condensed Financial Information of U-Haul Holding Company Parent Company Only (Narratives) (Details) - Private placements [Member] - U-Haul Holding Company [Member] - USD ($) $ in Millions	12 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Debt Instruments [Abstract]
Debt Instrument, Face Amount	$ 1,200.0
Minimum [Member]
Long-term Debt, Current Maturities [Abstract]
Maturity Year	2029	2030
Maximum [Member]
Long-term Debt, Current Maturities [Abstract]
Maturity Year	2035	2035