Condensed Financial Information of AMERCO, Statements of Operations (Details) (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2012
Revenues:
Net interest income from subsidiaries	$ 2,835,252	$ 2,558,587	$ 2,512,027
Expenses:
Operating expenses	1,288,481	1,170,568	1,093,190
Total expenses	2,205,038	2,059,404	2,096,020
Equity in earnings of subsidiaries	0	0	0
Interest Income	92,692	90,696	90,371
Pretax earnings	537,522	408,487	325,636
Income tax expense	(195,131)	(143,779)	(120,269)
Net earnings	342,391	264,708	205,367
Less: Excess of redemption value over carrying value of preferred shares redeemed			(5,908)
Less: Preferred stock dividends			(2,913)
Earnings available to common shareholders	342,391	264,708	196,546
Basic and diluted earnings per common share	$ 17.51	$ 13.56	$ 10.09
Weighted average common shares outstanding: basic and diluted	19,558,758	19,518,779	19,476,187
AMERCO [Member]
Revenues:
Net interest income from subsidiaries	6,465	5,329	6,085
Expenses:
Operating expenses	6,636	13,611	9,081
Other expenses	97	97	98
Total expenses	6,733	13,708	9,179
Equity in earnings of subsidiaries	287,803	212,164	149,160
Interest Income	86,916	91,125	94,278
Pretax earnings	374,451	294,910	240,344
Income tax expense	(32,060)	(30,202)	(34,649)
Net earnings	342,391	264,708	205,695
Less: Excess of redemption value over carrying value of preferred shares redeemed			(5,908)
Less: Preferred stock dividends			(3,241)
Earnings available to common shareholders	$ 342,391	$ 264,708	$ 196,546
Basic and diluted earnings per common share	$ 17.51	$ 13.56	$ 10.09
Weighted average common shares outstanding: basic and diluted	19,558,758	19,518,779	19,476,187