Consolidated Statement of Operations by Industry Segment (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Jun. 30, 2013		Jun. 30, 2012
Revenues:
Self-moving equipment rentals	$ 521,649		$ 466,994
Self-storage revenues	42,099		34,736
Self-moving and self-storage products and service sales	70,691		67,178
Property management fees	5,161		4,860
Life insurance premiums	41,062		46,426
Property and casualty insurance premiums	7,966		7,243
Net investment and interest income	18,989		14,517
Other revenue	39,214		25,722
Total revenues	746,831		667,676
Costs and expenses:
Operating expenses	309,501		283,393
Commission expenses	68,627		61,107
Cost of sales	35,570		32,227
Benefits and losses	42,633		48,338
Amortization of deferred policy acquisition costs	3,683		2,811
Lease expense	27,007		32,796
Depreciation, net of (gains) losses on disposals	57,434		56,125
Total costs and expenses	544,455		516,797
Earnings from operations	202,376		150,879
Interest income (expense)	(23,328)		(23,491)
Total pretax earnings (loss)	179,048		127,388
Income tax expense	(66,080)		(46,819)
Net earnings	112,968		80,569
Earnings available to common shareholders	112,968		80,569
Operating Segments | Property and Casualty Insurance
Revenues:
Self-moving equipment rentals	0	[1]	0	[2]
Self-storage revenues	0	[1]	0	[2]
Self-moving and self-storage products and service sales	0	[1]	0	[2]
Property management fees	0	[1]	0	[2]
Life insurance premiums	0	[1]	0	[2]
Property and casualty insurance premiums	7,966	[1]	7,243	[2]
Net investment and interest income	2,477	[1]	2,200	[2]
Other revenue	0	[1]	0	[2]
Total revenues	10,443	[1]	9,443	[2]
Costs and expenses:
Operating expenses	4,096	[1]	3,290	[2]
Commission expenses	0	[1]	0	[2]
Cost of sales	0	[1]	0	[2]
Benefits and losses	1,957	[1]	3,566	[2]
Amortization of deferred policy acquisition costs	0	[1]	0	[2]
Lease expense	0	[1]	0	[2]
Depreciation, net of (gains) losses on disposals	0	[1]	0	[2]
Total costs and expenses	6,053	[1]	6,856	[2]
Earnings (loss) from operations before subsidiaries	4,390	[1]	2,587	[2]
Equity in earnings of subsidiaries	0	[1]	0	[2]
Earnings from operations	4,390	[1]	2,587	[2]
Interest income (expense)	0	[1]	0	[2]
Total pretax earnings (loss)	4,390	[1]	2,587	[2]
Income tax expense	(1,537)	[1]	(906)	[2]
Net earnings	2,853	[3]	1,681	[4]
Earnings available to common shareholders	2,853	[1]	1,681	[2]
Operating Segments | Life Insurance
Revenues:
Self-moving equipment rentals	0	[1]	0	[2]
Self-storage revenues	0	[1]	0	[2]
Self-moving and self-storage products and service sales	0	[1]	0	[2]
Property management fees	0	[1]	0	[2]
Life insurance premiums	41,062	[1]	46,426	[2]
Property and casualty insurance premiums	0	[1]	0	[2]
Net investment and interest income	13,222	[1]	9,270	[2]
Other revenue	495	[1]	446	[2]
Total revenues	54,779	[1]	56,142	[2]
Costs and expenses:
Operating expenses	6,360	[1]	7,155	[2]
Commission expenses	0	[1]	0	[2]
Cost of sales	0	[1]	0	[2]
Benefits and losses	40,676	[1]	44,772	[2]
Amortization of deferred policy acquisition costs	3,683	[1]	2,811	[2]
Lease expense	0	[1]	0	[2]
Depreciation, net of (gains) losses on disposals	0	[1]	0	[2]
Total costs and expenses	50,719	[1]	54,738	[2]
Earnings (loss) from operations before subsidiaries	4,060	[1]	1,404	[2]
Equity in earnings of subsidiaries	0	[1]	0	[2]
Earnings from operations	4,060	[1]	1,404	[2]
Interest income (expense)	0	[1]	0	[2]
Total pretax earnings (loss)	4,060	[1]	1,404	[2]
Income tax expense	(1,405)	[1]	(503)	[2]
Net earnings	2,655	[3]	901	[4]
Earnings available to common shareholders	2,655	[1]	901	[2]
Operating Segments | Moving and Storage Operating Segment
Revenues:
Self-moving equipment rentals	522,083		467,315
Self-storage revenues	42,099		34,736
Self-moving and self-storage products and service sales	70,691		67,178
Property management fees	5,161		4,860
Life insurance premiums	0		0
Property and casualty insurance premiums	0		0
Net investment and interest income	3,409		3,135
Other revenue	40,960		25,625
Total revenues	684,403		602,849
Costs and expenses:
Operating expenses	301,711		273,605
Commission expenses	68,627		61,107
Cost of sales	35,570		32,227
Benefits and losses	0		0
Amortization of deferred policy acquisition costs	0		0
Lease expense	27,053		32,826
Depreciation, net of (gains) losses on disposals	57,434		56,125
Total costs and expenses	490,395		455,890
Earnings (loss) from operations before subsidiaries	194,008		146,959
Equity in earnings of subsidiaries	5,508		2,582
Earnings from operations	199,516		149,541
Interest income (expense)	(23,410)		(23,562)
Total pretax earnings (loss)	176,106		125,979
Income tax expense	(63,138)		(45,410)
Net earnings	112,968		80,569
Earnings available to common shareholders	112,968		80,569
Operating Segments | Moving and Storage Operating Segment | AMERCO
Revenues:
Self-moving equipment rentals	0		0
Self-storage revenues	0		0
Self-moving and self-storage products and service sales	0		0
Property management fees	0		0
Life insurance premiums	0		0
Property and casualty insurance premiums	0		0
Net investment and interest income	1,238		1,253
Other revenue	0		81
Total revenues	1,238		1,334
Costs and expenses:
Operating expenses	2,221		3,462
Commission expenses	0		0
Cost of sales	0		0
Benefits and losses	0		0
Amortization of deferred policy acquisition costs	0		0
Lease expense	23		24
Depreciation, net of (gains) losses on disposals	1		1
Total costs and expenses	2,245		3,487
Earnings (loss) from operations before subsidiaries	(1,007)		(2,153)
Equity in earnings of subsidiaries	99,795		66,615
Earnings from operations	98,788		64,462
Interest income (expense)	21,932		24,660
Total pretax earnings (loss)	120,720		89,122
Income tax expense	(7,752)		(8,553)
Net earnings	112,968		80,569
Earnings available to common shareholders	112,968		80,569
Operating Segments | Moving and Storage Operating Segment | U-Haul
Revenues:
Self-moving equipment rentals	522,083		467,315
Self-storage revenues	41,822		34,452
Self-moving and self-storage products and service sales	70,691		67,178
Property management fees	5,161		4,860
Life insurance premiums	0		0
Property and casualty insurance premiums	0		0
Net investment and interest income	2,170		1,688
Other revenue	42,530		27,167
Total revenues	684,457		602,660
Costs and expenses:
Operating expenses	323,007		290,311
Commission expenses	68,627		61,107
Cost of sales	35,570		32,227
Benefits and losses	0		0
Amortization of deferred policy acquisition costs	0		0
Lease expense	26,998		32,797
Depreciation, net of (gains) losses on disposals	54,166		52,320
Total costs and expenses	508,368		468,762
Earnings (loss) from operations before subsidiaries	176,089		133,898
Equity in earnings of subsidiaries	0		0
Earnings from operations	176,089		133,898
Interest income (expense)	(30,044)		(34,154)
Total pretax earnings (loss)	146,045		99,744
Income tax expense	(53,996)		(36,413)
Net earnings	92,049		63,331
Earnings available to common shareholders	92,049		63,331
Operating Segments | Moving and Storage Operating Segment | Real Estate
Revenues:
Self-moving equipment rentals	0		0
Self-storage revenues	277		284
Self-moving and self-storage products and service sales	0		0
Property management fees	0		0
Life insurance premiums	0		0
Property and casualty insurance premiums	0		0
Net investment and interest income	1		194
Other revenue	24,569		21,085
Total revenues	24,847		21,563
Costs and expenses:
Operating expenses	2,622		2,540
Commission expenses	0		0
Cost of sales	0		0
Benefits and losses	0		0
Amortization of deferred policy acquisition costs	0		0
Lease expense	32		5
Depreciation, net of (gains) losses on disposals	3,267		3,804
Total costs and expenses	5,921		6,349
Earnings (loss) from operations before subsidiaries	18,926		15,214
Equity in earnings of subsidiaries	0		0
Earnings from operations	18,926		15,214
Interest income (expense)	(15,298)		(14,068)
Total pretax earnings (loss)	3,628		1,146
Income tax expense	(1,390)		(444)
Net earnings	2,238		702
Earnings available to common shareholders	2,238		702
Operating Segments | Moving and Storage Operating Segment | Moving and Storage Operating Eliminations
Revenues:
Self-moving equipment rentals	0		0
Self-storage revenues	0		0
Self-moving and self-storage products and service sales	0		0
Property management fees	0		0
Life insurance premiums	0		0
Property and casualty insurance premiums	0		0
Net investment and interest income	0		0
Other revenue	(26,139)		(22,708)
Total revenues	(26,139)		(22,708)
Costs and expenses:
Operating expenses	(26,139)		(22,708)
Commission expenses	0		0
Cost of sales	0		0
Benefits and losses	0		0
Amortization of deferred policy acquisition costs	0		0
Lease expense	0		0
Depreciation, net of (gains) losses on disposals	0		0
Total costs and expenses	(26,139)		(22,708)
Earnings (loss) from operations before subsidiaries	0		0
Equity in earnings of subsidiaries	(94,287)		(64,033)
Earnings from operations	(94,287)		(64,033)
Interest income (expense)	0		0
Total pretax earnings (loss)	(94,287)		(64,033)
Income tax expense	0		0
Net earnings	(94,287)		(64,033)
Earnings available to common shareholders	(94,287)		(64,033)
Eliminations
Revenues:
Self-moving equipment rentals	(434)	[5]	(321)	[5]
Self-storage revenues	0		0
Self-moving and self-storage products and service sales	0		0
Property management fees	0		0
Life insurance premiums	0		0
Property and casualty insurance premiums	0		0
Net investment and interest income	(119)	[6]	(88)	[6]
Other revenue	(2,241)	[6]	(349)	[6]
Total revenues	(2,794)		(758)
Costs and expenses:
Operating expenses	(2,666)	[5],[6],[7]	(657)	[5],[6],[8]
Commission expenses	0		0
Cost of sales	0		0
Benefits and losses	0		0
Amortization of deferred policy acquisition costs	0		0
Lease expense	(46)	[6]	(30)	[6]
Depreciation, net of (gains) losses on disposals	0		0
Total costs and expenses	(2,712)		(687)
Earnings (loss) from operations before subsidiaries	(82)		(71)
Equity in earnings of subsidiaries	(5,508)	[9]	(2,582)	[9]
Earnings from operations	(5,590)		(2,653)
Interest income (expense)	82	[6]	71	[6]
Total pretax earnings (loss)	(5,508)		(2,582)
Income tax expense	0		0
Net earnings	(5,508)		(2,582)
Earnings available to common shareholders	$ (5,508)		$ (2,582)

[1] Balances for the quarter ended March 31, 2013

[2] Balance for the quarter ended March 31, 2012

[3] Balance for the period ended March 31, 2013

[4] Balance for the period ended March 31, 2012

[5] Eliminate intercompany premiums

[6] Eliminate intercompany lease / interest income

[7] Eliminate investment in subsidiaries

[8] Eliminate intercompany receivables and payables

[9] Eliminate equity in earnings of subsidiaries