Long-term Debt Borrowings, Text Portion (Details) (USD $)			3 Months Ended
	Jun. 30, 2013	Mar. 31, 2013	Jun. 30, 2013 Amerco Real Estate, Subsidiaries, and U-Haul Co. of Florida Mortgages U-Haul Guarantor	Jun. 30, 2013 Amerco Real Estate and Subsidiaries of U-Haul Int'l Construction Loans U-Haul Int'l and Amerco Guarantor	Jun. 30, 2013 Amerco Real Estate and U-Haul Company of Florida Line of Credit U-Haul Int'l and Amerco Guarantor	Jun. 30, 2013 Various Subsidiaries of Amerco Real Estate and U-Haul Int'l Senior Mortgage Amerco Real Estate and U-Haul Int'l Guarantor	Jun. 30, 2013 Amerco Real Estate Company Capital Lease Obligations U-Haul Int'l and Amerco Guarantor	Jun. 30, 2013 U-Haul Int'l and Subsidiaries Rental Truck (Amortizing Credit) First Loan U-Haul Int'l and Amerco Guarantor	Jun. 30, 2013 U-Haul Int'l and Subsidiaries Rental Truck (Amortizing Credit) Second Loan U-Haul Int'l and Amerco Guarantor	Jun. 30, 2013 Subsidiaries of U-Haul Int'l Cargo Van and Pickup Acquisitions Amerco Real Estate and U-Haul Int'l Guarantor	Jun. 30, 2013 U-Haul S Fleet, 2007 Box Truck Note Securitization First Loan	Jun. 30, 2013 U-Haul S Fleet, 2010 Box Truck Note Securitization Second Loan	Jun. 30, 2013 AMERCO Capital Leases for New Equipment	Jun. 30, 2013 Amerco and US Bank, National Association, the Trustee U-Haul Investor Club
Debt instruments, interest rate, stated percentage:
Debt instrument, interest rate, stated percentage			6.93%								5.56%	4.90%
Debt instrument, interest rate, stated percentage rate range, minimum						4.90%		2.82%	1.95%	3.52%				3.00%
Debt instrument, interest rate, stated percentage rate range, maximum						5.75%		6.92%	3.94%	3.53%				8.00%
Debt instruments, interest rate, effective percentage:
LIBOR			0.20%	0.19%				0.19%
LIBOR - highest rate								0.20%
Applicable margin interest rate			1.50%	1.90%	1.25%		1.25%
Debt instrument, interest rate at period end			1.70%	2.09%
Applicable margin, per loan agreement, minimum rate								0.90%
Applicable margin, per loan agreement, maximum rate								2.63%
Applicable margins, low rate								0.90%
Applicable margins, high rate								2.63%
Debt instruments, face, payment, and remaining balance amount:
Debt instrument, face amount										$ 115,000,000
Debt instrument, original face amount										85,000,000
Debt instrument, increase in face amount										95,000,000
Debt instrument, associate another note amount										20,000,000
Line of credit facility, maximum borrowing capacity				26,100,000	100,000,000		25,000,000				217,000,000	155,000,000
Line of credit, current borrowing capacity					50,000,000		25,000,000
Line of credit facility, remaining borrowing capacity					50,000,000
Notes, loans and leases payable	1,737,277,000	1,661,845,000	257,500,000	24,400,000		550,900,000		254,800,000	59,800,000	115,000,000	78,600,000	103,800,000	323,000,000	35,700,000
Subsidiary holdings of parent company debt														$ 6,400,000
Debt instruments, issuance and maturity dates:
Mortgage loans on real estate, final maturity date			Apr. 30, 2023	Jun. 30, 2016	Apr. 30, 2014
Debt instrument, maturity date							Apr. 30, 2015			Aug. 26, 2016	Feb. 25, 2014	Oct. 25, 2017
Debt instrument, maturity date range, start						Jul. 01, 2015		Jul. 31, 2013	Jul. 31, 2013					Jun. 30, 2013
Debt instrument, maturity date range, end						Oct. 11, 2038		May 31, 2020	May 31, 2020					May 31, 2043
Debt instrument, issuance date				Jun. 29, 2006	Apr. 29, 2011					Dec. 31, 2009	Jun. 01, 2007	Oct. 28, 2010		Feb. 28, 2011
Loan modification and extension date				Jun. 27, 2011						May 31, 2017
Term note amended date					Feb. 28, 2013		Feb. 28, 2013			Aug. 26, 2011
Debt instrument, earliest issuance date													Apr. 29, 2008
Debt instrument, latest issuance date										Dec. 22, 2011			May 31, 2013
Purchase equipment through fiscal year											2008
Debt instruments, miscellaneous information:
Terms of lease													Between 3 and 7 years
Optional extension					1 year 0 months 0 days