Schedule I - Condensed Financial Information Of AMERCO (Statements of Comprehensive Income) (Details) - USD ($) $ in Thousands	12 Months Ended
Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2016
Net earnings	$ 790,583	$ 398,424	$ 489,001
Amerco [Member]
Net earnings	790,583	398,424	489,001
Other comprehensive income (loss)	37,873	9,289	(26,160)
Total comprehensive income	$ 828,456	$ 407,713	$ 462,841

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
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