Consolidated Statement of Operations by Industry Segment (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Mar. 31, 2014		Mar. 31, 2013		Mar. 31, 2012
Revenues:
Self-moving equipment rentals	$ 1,955,423		$ 1,767,520		$ 1,678,256
Self-storage revenues	181,794		152,660		134,376
Self-moving and self-storage products and service sales	234,187		221,117		213,854
Property management fees	24,493		24,378		23,266
Life insurance premiums	157,919		178,115		277,562
Property and casualty insurance premiums	41,052		34,342		32,631
Net investment and interest income	79,591		82,903		73,552
Other revenue	160,793		97,552		78,530
Total revenues	2,835,252		2,558,587		2,512,027
Costs and expenses:
Operating expenses	1,288,481		1,170,568		1,093,190
Commission expenses	252,525		228,124		212,190
Cost of sales	127,270		107,216		116,542
Benefits and losses	156,702		180,676		320,191
Amortization of deferred policy acquisition costs	19,982		17,376		13,791
Lease expense	100,466		117,448		131,215
Depreciation, net of (gains) losses on disposals	259,612		237,996		208,901
Total expenses	2,205,038		2,059,404		2,096,020
Earnings (loss) from operations before subsidiaries	630,214		499,183		416,007
Equity in earnings of subsidiaries	0		0		0
Earnings from operations	630,214		499,183		416,007
Interest income (expense)	(92,692)		(90,696)		(90,371)
Total 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)
Preferred stock dividends paid					(2,913)
Earnings available to common shareholders	342,391		264,708		196,546
AMERCO [Member]
Revenues:
Total revenues	6,465		5,329		6,085
Costs and expenses:
Operating expenses	6,636		13,611		9,081
Total expenses	6,733		13,708		9,179
Equity in earnings of subsidiaries	287,803		212,164		149,160
Interest income (expense)	(86,916)		(91,125)		(94,278)
Total 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)
Preferred stock dividends paid					(3,241)
Earnings available to common shareholders	342,391		264,708		196,546
Eliminations
Revenues:
Self-moving equipment rentals	(2,786)	[1]	(1,538)		(1,707)	[1]
Self-storage revenues	0		0		0
Self-moving and self-storage products and service sales	0		0		0
Property management fees	0		0		0
Life insurance premiums	0		0		0
Property and casualty insurance premiums	0		0		0
Net investment and interest income	(611)	[2]	(427)	[2]	(1,662)	[2],[3],[4]
Other revenue	(473)	[2]	(1,480)	[2]	(1,387)	[2]
Total revenues	(3,870)		(3,445)		(4,756)
Costs and expenses:
Operating expenses	(3,217)	[1],[2],[4]	(2,984)	[1],[2],[4]	(3,087)	[1],[2],[4]
Commission expenses	0		0		0
Cost of sales	0		0		0
Benefits and losses	0		0		0
Amortization of deferred policy acquisition costs	0		0		0
Lease expense	(183)	[2]	(167)	[2]	(1,187)	[2]
Depreciation, net of (gains) losses on disposals	0		0		0
Total expenses	(3,400)		(3,151)		(4,274)
Earnings (loss) from operations before subsidiaries	(470)		(294)		(482)
Equity in earnings of subsidiaries	(29,992)	[5]	(24,241)	[5]	10,378	[5]
Earnings from operations	(30,462)		(24,535)		9,896
Interest income (expense)	470	[2]	294	[2]	154	[2]
Total pretax earnings	(29,992)		(24,241)		10,050
Income tax expense	0		0		0
Net earnings	(29,992)		(24,241)		10,050
Less: Excess of redemption value over carrying value of preferred shares redeemed					0
Preferred stock dividends paid					328	[3]
Earnings available to common shareholders	(29,992)		(24,241)		10,378
Property and Casualty Insurance [Member] | Operating Segments [Member]
Revenues:
Self-moving equipment rentals	0	[6]	0	[7]	0	[8]
Self-storage revenues	0	[6]	0	[7]	0	[8]
Self-moving and self-storage products and service sales	0	[6]	0	[7]	0	[8]
Property management fees	0	[6]	0	[7]	0	[8]
Life insurance premiums	0	[6]	0	[7]	0	[8]
Property and casualty insurance premiums	41,052	[6]	34,342	[7]	32,631	[8]
Net investment and interest income	10,592	[6]	13,858	[7]	9,955	[8]
Other revenue	0	[6]	0	[7]	0	[8]
Total revenues	51,644	[6]	48,200	[7]	42,586	[8]
Costs and expenses:
Operating expenses	20,799	[6]	18,007	[7]	13,270	[8]
Commission expenses	0	[6]	0	[7]	0	[8]
Cost of sales	0	[6]	0	[7]	0	[8]
Benefits and losses	11,513	[6]	15,999	[7]	65,742	[8]
Amortization of deferred policy acquisition costs	0	[6]	0	[7]	0	[8]
Lease expense	0	[6]	0	[7]	0	[8]
Depreciation, net of (gains) losses on disposals	0	[6]	0	[7]	0	[8]
Total expenses	32,312	[6]	34,006	[7]	79,012	[8]
Earnings (loss) from operations before subsidiaries	19,332	[6]	14,194	[7]	(36,426)	[8]
Equity in earnings of subsidiaries	0	[6]	0	[7]	0	[8]
Earnings from operations	19,332	[6]	14,194	[7]	(36,426)	[8]
Interest income (expense)	0	[6]	0	[7]	0	[8]
Total pretax earnings	19,332	[6]	14,194	[7]	(36,426)	[8]
Income tax expense	(6,670)	[6]	(4,938)	[7]	12,863	[8]
Net earnings	12,662		9,256	[9]	(23,563)	[8]
Less: Excess of redemption value over carrying value of preferred shares redeemed					0	[8]
Preferred stock dividends paid					0	[8]
Earnings available to common shareholders	12,662	[6]	9,256	[7]	(23,563)	[8]
Life Insurance [Member] | Operating Segments [Member]
Revenues:
Self-moving equipment rentals	0	[6]	0	[7]	0	[8]
Self-storage revenues	0	[6]	0	[7]	0	[8]
Self-moving and self-storage products and service sales	0	[6]	0	[7]	0	[8]
Property management fees	0	[6]	0	[7]	0	[8]
Life insurance premiums	157,919	[6]	178,115	[7]	277,562	[8]
Property and casualty insurance premiums	0	[6]	0	[7]	0	[8]
Net investment and interest income	54,398	[6]	50,850	[7]	38,127	[8]
Other revenue	3,211	[6]	2,525	[7]	1,585	[8]
Total revenues	215,528	[6]	231,490	[7]	317,274	[8]
Costs and expenses:
Operating expenses	23,686	[6]	26,482	[7]	28,885	[8]
Commission expenses	0	[6]	0	[7]	0	[8]
Cost of sales	0	[6]	0	[7]	0	[8]
Benefits and losses	145,189	[6]	164,677	[7]	254,449	[8]
Amortization of deferred policy acquisition costs	19,982	[6]	17,376	[7]	13,791	[8]
Lease expense	0	[6]	0	[7]	0	[8]
Depreciation, net of (gains) losses on disposals	0	[6]	0	[7]	0	[8]
Total expenses	188,857	[6]	208,535	[7]	297,125	[8]
Earnings (loss) from operations before subsidiaries	26,671	[6]	22,955	[7]	20,149	[8]
Equity in earnings of subsidiaries	0	[6]	0	[7]	0	[8]
Earnings from operations	26,671	[6]	22,955	[7]	20,149	[8]
Interest income (expense)	0	[6]	0	[7]	0	[8]
Total pretax earnings	26,671	[6]	22,955	[7]	20,149	[8]
Income tax expense	(9,341)	[6]	(7,970)	[7]	(6,964)	[8]
Net earnings	17,330		14,985	[9]	13,185	[8]
Less: Excess of redemption value over carrying value of preferred shares redeemed					0	[8]
Preferred stock dividends paid					0	[8]
Earnings available to common shareholders	17,330	[6]	14,985	[7]	13,185	[8]
Moving and Storage Operating Segment | Operating Segments [Member]
Revenues:
Self-moving equipment rentals	1,958,209		1,769,058		1,679,963
Self-storage revenues	181,794		152,660		134,376
Self-moving and self-storage products and service sales	234,187		221,117		213,854
Property management fees	24,493		24,378		23,266
Life insurance premiums	0		0		0
Property and casualty insurance premiums	0		0		0
Net investment and interest income	15,212		18,622		27,132
Other revenue	158,055		96,507		78,332
Total revenues	2,571,950		2,282,342		2,156,923
Costs and expenses:
Operating expenses	1,247,213		1,129,063		1,054,122
Commission expenses	252,525		228,124		212,190
Cost of sales	127,270		107,216		116,542
Benefits and losses	0		0		0
Amortization of deferred policy acquisition costs	0		0		0
Lease expense	100,649		117,615		132,402
Depreciation, net of (gains) losses on disposals	259,612		237,996		208,901
Total expenses	1,987,269		1,820,014		1,724,157
Earnings (loss) from operations before subsidiaries	584,681		462,328		432,766
Equity in earnings of subsidiaries	29,992		24,241		(10,378)
Earnings from operations	614,673		486,569		422,388
Interest income (expense)	(93,162)		(90,990)		(90,525)
Total pretax earnings	521,511		395,579		331,863
Income tax expense	(179,120)		(130,871)		(126,168)
Net earnings	342,391		264,708		205,695
Less: Excess of redemption value over carrying value of preferred shares redeemed					(5,908)
Preferred stock dividends paid					(3,241)
Earnings available to common shareholders	342,391		264,708		196,546
Moving and Storage Operating Segment | Operating Segments [Member] | Moving and Storage Operating Eliminations
Revenues:
Self-moving equipment rentals	0		0		0
Self-storage revenues	0		0		0
Self-moving and self-storage products and service sales	0		0		0
Property management fees	0		0		0
Life insurance premiums	0		0		0
Property and casualty insurance premiums	0		0		0
Net investment and interest income	0		0		0
Other revenue	(110,111)	[2]	(94,976)	[2]	(86,108)	[2]
Total revenues	(110,111)		(94,976)		(86,108)
Costs and expenses:
Operating expenses	(110,111)	[2]	(94,976)	[2]	(86,108)	[2]
Commission expenses	0		0		0
Cost of sales	0		0		0
Benefits and losses	0		0		0
Amortization of deferred policy acquisition costs	0		0		0
Lease expense	0		0		0
Depreciation, net of (gains) losses on disposals	0		0		0
Total expenses	(110,111)		(94,976)		(86,108)
Earnings (loss) from operations before subsidiaries	0		0		0
Equity in earnings of subsidiaries	(257,811)	[5]	(187,923)	[5]	(159,538)	[5]
Earnings from operations	(257,811)		(187,923)		(159,538)
Interest income (expense)	0		0		0
Total pretax earnings	(257,811)		(187,923)		(159,538)
Income tax expense	0		0		0
Net earnings	(257,811)		(187,923)		(159,538)
Less: Excess of redemption value over carrying value of preferred shares redeemed					0
Preferred stock dividends paid					0
Earnings available to common shareholders	(257,811)		(187,923)		(159,538)
Moving and Storage Operating Segment | Operating Segments [Member] | AMERCO [Member]
Revenues:
Self-moving equipment rentals	0		0		0
Self-storage revenues	0		0		0
Self-moving and self-storage products and service sales	0		0		0
Property management fees	0		0		0
Life insurance premiums	0		0		0
Property and casualty insurance premiums	0		0		0
Net investment and interest income	6,205		5,248		5,857
Other revenue	260		81		228
Total revenues	6,465		5,329		6,085
Costs and expenses:
Operating expenses	6,636		13,611		9,081
Commission expenses	0		0		0
Cost of sales	0		0		0
Benefits and losses	0		0		0
Amortization of deferred policy acquisition costs	0		0		0
Lease expense	92		92		93
Depreciation, net of (gains) losses on disposals	5		5		5
Total expenses	6,733		13,708		9,179
Earnings (loss) from operations before subsidiaries	(268)		(8,379)		(3,094)
Equity in earnings of subsidiaries	287,803		212,164		149,160
Earnings from operations	287,535		203,785		146,066
Interest income (expense)	86,916		91,125		94,278
Total 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)
Preferred stock dividends paid					(3,241)
Earnings available to common shareholders	342,391		264,708		196,546
Moving and Storage Operating Segment | Operating Segments [Member] | Uhaul [Member]
Revenues:
Self-moving equipment rentals	1,958,209		1,769,058		1,679,963
Self-storage revenues	180,592		151,512		133,070
Self-moving and self-storage products and service sales	234,187		221,117		213,854
Property management fees	24,493		24,378		23,266
Life insurance premiums	0		0		0
Property and casualty insurance premiums	0		0		0
Net investment and interest income	8,107		8,462		20,577
Other revenue	164,450		102,776		83,894
Total revenues	2,570,038		2,277,303		2,154,624
Costs and expenses:
Operating expenses	1,338,635		1,199,550		1,121,681
Commission expenses	252,525		228,124		212,190
Cost of sales	127,270		107,216		116,542
Benefits and losses	0		0		0
Amortization of deferred policy acquisition costs	0		0		0
Lease expense	100,521		117,491		132,286
Depreciation, net of (gains) losses on disposals	242,721		224,407		195,469
Total expenses	2,061,672		1,876,788		1,778,168
Earnings (loss) from operations before subsidiaries	508,366		400,515		376,456
Equity in earnings of subsidiaries	0		0		0
Earnings from operations	508,366		400,515		376,456
Interest income (expense)	(110,270)		(124,012)		(132,781)
Total pretax earnings	398,096		276,503		243,675
Income tax expense	(144,465)		(96,099)		(88,096)
Net earnings	253,631		180,404		155,579
Less: Excess of redemption value over carrying value of preferred shares redeemed					0
Preferred stock dividends paid					0
Earnings available to common shareholders	253,631		180,404		155,579
Moving and Storage Operating Segment | Operating Segments [Member] | Real Estate [Member]
Revenues:
Self-moving equipment rentals	0		0		0
Self-storage revenues	1,202		1,148		1,306
Self-moving and self-storage products and service sales	0		0		0
Property management fees	0		0		0
Life insurance premiums	0		0		0
Property and casualty insurance premiums	0		0		0
Net investment and interest income	900		4,912		698
Other revenue	103,456		88,626		80,318
Total revenues	105,558		94,686		82,322
Costs and expenses:
Operating expenses	12,053		10,878		9,468
Commission expenses	0		0		0
Cost of sales	0		0		0
Benefits and losses	0		0		0
Amortization of deferred policy acquisition costs	0		0		0
Lease expense	36		32		23
Depreciation, net of (gains) losses on disposals	16,886		13,584		13,427
Total expenses	28,975		24,494		22,918
Earnings (loss) from operations before subsidiaries	76,583		70,192		59,404
Equity in earnings of subsidiaries	0		0		0
Earnings from operations	76,583		70,192		59,404
Interest income (expense)	(69,808)		(58,103)		(52,022)
Total pretax earnings	6,775		12,089		7,382
Income tax expense	(2,595)		(4,570)		(3,423)
Net earnings	4,180		7,519		3,959
Less: Excess of redemption value over carrying value of preferred shares redeemed					0
Preferred stock dividends paid					0
Earnings available to common shareholders	$ 4,180		$ 7,519		$ 3,959

[1] Eliminate intercompany premiums

[2] Eliminate intercompany lease / interest income

[3] Elimination of preferred stock dividend paid to affiliate

[4] The earned and written premiums are reported net of intersegment transactions. There were no earned premiums eliminated for the years ended December 31, 2013, 2012 and 2011, respectively.

[5] Eliminate equity in earnings of subsidiaries

[6] Balances as of December 31, 2013

[7] Balances as of December 31, 2012

[8] Balances for the year ended December 31, 2011

[9] Balance for the period ended December 31, 2012