Schedule I - Condensed Financial Information Of AMERCO (Statements of Comprehensive Income) (Details) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2017
Net earnings	$ 370,857	$ 790,583	$ 398,424
Amerco [Member]
Net earnings	370,857	790,583	398,424
Other comprehensive income (loss)	(62,075)	37,873	9,289
Total comprehensive income	$ 308,782	$ 828,456	$ 407,713