CANADA Canada [Member] UNITED STATES United States [Member] Amendment Description Amendment Flag Current Fiscal Year End Date Document Fiscal Period Focus Document Fiscal Year Focus Document Period End Date Document Type Entity Central Index Key Entity Common Stock, Shares Outstanding Entity Current Reporting Status Entity [Domain] AMERCO Consolidated Entity Filer Category Entity Public Float Entity Registrant Name Entity Voluntary Filers Entity Well-known Seasoned Issuer Legal Entity [Axis] A roll forward schedule of the summary of accumulated other comprehensive income (loss) components, net of tax. Accumulated Other Comprehensive Income (Loss) Components, Net of Tax [Roll Forward] AMERCO /NV/ is the controlling legal entity for the entire enterprise. Within the corporation, distinct financial reports also separate AMERCO from its other business segments. In order to capture this, we have defined under the Segments [Axis] / Segment [Domain] this extended concept: Amerco, Business Segment [Member] Amerco, Business Segment [Member] AMERCO [Member] Affiliates of Amerco with outstanding revolving credit construction loans Amerco Real Estate and Subsidiaries of Uhaul Intl [Member] Amerco Real Estate and Subsidiaries of U-Haul Int'l U-Haul International, North America's largest "do-it-yourself" moving and storage operator. Amerco Real Estate and Uhaul Intl [Member] Amerco Real Estate and U-Haul Int'l Guarantor [Member] Subsidiary company associated with an asset-backed working capital loan. Amerco Real Estate Company [Member] Amerco Real Estate Company Affiliates of Amerco with outstanding Real Estate loans. Amerco Real Estate Subsidiaries and Uhaul Company of Florida [Member] Amerco Real Estate, Subsidiaries, and U-Haul Co. of Florida Combination of Amerco's subsidiaries associated with revolving credit agreement with an option for a one year extension Amerco Real Estate, Uhaul Company Florida [Member] Amerco Real Estate and U-Haul Company of Florida Cannot use the same member in two different schedule with this software. The Long-term debt schedule uses UhaulIntlAmercoMember. These two members are the same. Amerco, Uhaul Intl [Member] Amerco, U-Haul Int'l The Company and associates offering U-Notes secured by various types of collateral including rental equipment and real estate. Amerco, Us Bank, National Association, Trustee [Member] Amerco and US Bank, National Association, the Trustee Fleet loan provision specified LIBOR plus applicable margin. This is the highest of the two applicable margin rates at the time of the loan agreement. Applicable Margin, Per Loan Agreement, Maximum Rate Applicable margin, per loan agreement, maximum rate Fleet loan provision specified LIBOR plus applicable margin. This is the lower of the two applicable margin rates at the time of the loan agreement. Applicable Margin, Per Loan Agreement, Minimum Rate Applicable margin, per loan agreement, minimum rate Sum of LIBOR and margin, at the higher of the rate. Applicable Margins, High Rate Sum of LIBOR and margin, maximum rate This is the sum of LIBOR and margin, at the lower of the rate range. Applicable Margins, Low Rate Sum of LIBOR and margin, minimum rate A borrowing recorded for a lease meeting the criteria for capitalization. Capital Lease [Member] Capital leases (rental equipment) [Member] Capital lease obligations for new equipment between dates with specific leasing terms. Capital Leases for New Equipment [Member] Capital Leases for New Equipment A subsidiary of U-Haul International has a term loan funding cargo van and pickup acquisitions. Cargo Van and Pickup Acquisitions [Member] Cargo Van and Pickup Acquisitions Cash generated from agreements and notes with SAC Holdings, Four SAC, Five SAC, Galaxy and Private Mini, excluding Dealer Agreements. Cash Generated from Agreements and Notes Cash flow, related party These agreements and notes with subsidiaries of SAC Holdings, 4 SAC, 5 SAC, Galaxy and Private Mini, Excluded Dealer Agreements commission expenses. Commission Expenses, Generated from Dealer Agreement with Related Party Commission expenses, generated from dealer agreement with related parties Fair value of common stock at quoted prices in active markets. Common Stock, Fair Value Disclosure Common stock Listed separately the common and preferred stock shares and amounts in treasury. Common Stock in Treasury [Member] Cost of common shares in treasury, net (22,377,912 shares as of June 30 and March 31, 2013) Cost of common shares in treasury, net The stated principal amount of the debt instrument includes a new note added during the life of the debt, which may vary from the carrying amount because of unamortized premium or discount. Debt Instrument, Associate Another Note Amount Debt instrument, associate another note amount Earliest date the capital lease obligation was issued. Debt Instrument, Earliest Issuance Date Debt instrument, earliest issuance date The stated principal amount of the debt instrument increased some time during the life of the debt, which may vary from the carrying amount because of unamortized premium or discount. Debt Instrument, Increase in Face Amount Debt instrument, increase in face amount Latest date the capital lease obligation was issued. Debt Instrument, Latest Issuance Date Debt instrument, latest issuance date The debt agreement amount at the beginning of this contract. It is no longer valid because of a subsequent amendment in the terms of this loan. Debt Instrument, Original Face Amount Debt instrument, original face amount This company-specific concept is a combination of three us-gaap taxonomy concepts. (1) Depreciation: "The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation." (2) Gain (Loss) on Disposition of Assets: "The gains and losses included in earnings resulting from the sale or disposal of tangible assets." (3) Deferred Policy Acquisition Cost Amortization Expense: "Amount of deferred policy acquisition costs charged to expense in the period, generally in proportion to related revenue earned, estimated gross profits, or over the customer relationship or some other period." Depreciation and Amortization, Net of (Gains) Losses on Disposals Depreciation and amortization, net of (gains) losses on disposals Depreciation and amortization, net of (gains) losses on disposals This company-specific concept is a combination of two US-GAAP taxonomy concepts. (1) Depreciation: "The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation." (2) Gain (Loss) on Disposition of Assets: "The gains and losses included in earnings resulting from the sale or disposal of tangible assets." Depreciation, Net of Gains (Losses) on Disposals Depreciation, net of (gains) losses on disposals Depreciation, net of (gains) on disposals (($7,917) and ($8,921),respectively) The date the derivative agreement becomes effective. This date differs from the agreement date. Derivative Effective Date Effective date Date the derivative is designated as a cash flow hedge. Designated Cash Flow Hedge Date Designed cash flow hedge date Document and Entity Information [Abstract] The Company has not provided financial or other support explicitly or implicitly during the period ended to any of these entities that it was not previously contractually required to provide. The carrying amount and the classification of assets and liabilities in the Company's balance sheet that related to the Company's variable interest in the Blackwater's entities are noted here, which approximate the maximum exposure to loss as a result of the Company's involvement with these entities. Due from Related Party, Recap of Assets [Text Block] Due from Related Party, Recap of Assets The Segmented Cash Flow statement contains a breakout of earnings from consolidated entities. The Consolidated Cash Flow Statement does not contain this concept, but both of these groups (roles) use the same calculation, so need to include this concept in both groups (roles). Earnings from Consolidated Entities Earnings from consolidated entities Earnings from consolidated entities Effect of Interest Rate Contracts [Abstract] The effect of interest rate contracts on the statement of operations: Fair Value, Fixed Maturities Asset Backed Securities with other-then-temporary impairment. Fixed Maturities - Asset Backed Securities capitalized interest Fixed maturities - asset backed securities OTTI (1) U-Haul International, Inc. and several of its subsidiaries are borrowers under amortizing term loans. The Amortizing Loans require monthly principal and interest payments, with the unpaid loan balance and accrued and unpaid interest due at maturity. These loans were used to purchase new trucks. The interest rates, per the provision of the Loan Agreement, are the applicable LIBOR plus a margin range. The interest rates are hedged with interest rate swaps based on current margins. Additionally, a specific amount of these loans are carried at a fixed rate. AMERCO and U-Haul International, Inc. are guarantors of these loans. The default provisions of these loans include non-payment of principal or interest and other standard reporting and change-in-control covenants. (2) A subsidiary of U-Haul International entered into a term note that was used to fund cargo van and pickup acquisitions for the past two years. These notes are secured by the purchased equipment and the corresponding operating cash flows associated with their operation. These notes have fixed interest rate. AMERCO and U-Haul International, Inc. are guarantors of this loan. The default provisions of these loans include non-payment of principal or interest and other standard reporting and change-in-control covenants. Fleet Loan, Amortizing Term [Member] Fleet loans (amortizing term) [Member] U-Haul S Fleet and its subsidiaries (collectively, "USF") issued asset-backed notes ("2007 Box Truck Note") and ("2010 Box Truck Note"). USF is a bankruptcy-remote special purpose entity wholly-owned by U-Haul International, Inc. The net proceeds from the securitized transaction were used to finance new box truck purchases. U. S. Bank, NA acts as the trustee for this securitization. These notes have fixed interest rates. The notes are secured by the box trucks that were purchased and the corresponding operating cash flows associated with their operation. Fleet Loan, Securitization [Member] Fleet loans (securitization) [Member] The revolver requires monthly interest payments only for the first four years and principal and interest payments due over the last nine months. The interest rates, per the provision of the revolving fleet loan are the applicable LIBOR plus a margin. Fleet Loans Revolving Credit [Member] Fleet loans (revolving credit) [Member] We used "AvailableForSaleSecuritiesGrossUnrealizedGainLoss" in prior filings for this concept, but the 2013 taxonomy deprecated the above concept and created a new one with the period type changed to 'duration.' We must have an 'instant' period type in order to complete the calculation within this schedule. This is the unrealized gain on all our available-for-sale investments as of the quarter ending date. Gross Unrealized Gains Gross unrealized gains We include two different LIBOR rates for these loans in our documentation. High Libor Rate LIBOR - highest rate This is a primary concept, which incorporates two US-GAAP concepts: (1) IncreaseDecreaseInReinsuranceRecoverable with the definition "the increase (decrease) during the reporting period in the amount of benefits the ceding insurer expects to recover on insurance policies ceded to other insurance entities as of the balance sheet date for all guaranteed benefit types." (2) IncreaseDecreaseInReceivables with the definition: "The increase (decrease) during the reporting period in the total amount due within one year (or one operating cycle) from all parties, associated with underlying transactions that are classified as operating activities." Increase (Decrease) in Reinsurance Recoverables and Receivables Reinsurance recoverables and trade receivables This insurance grouping includes RepWest and Oxford Life Insurance. Insurance Group [Member] Insurance group Our disclosure provides for only the interest expense on borrowings. Within the US-GAAP taxonomy, there is an Interest Income and Interest Expense Disclosure [Text Block], but nothing that specifically covers only Interest Expense. Interest Expense Disclosure [Text Block] Interest expense disclosure Interest Expense We provide the largest aggregate amount of related party notes receivable that occurred during this reporting period. This can be compared to the related party notes receivable balance at the end of this period. Largest Aggregate Balance in Reporting Period Largest aggregate balance in reporting period Month, day and year in which the contingent legal matter will be considered in a court of law or other jurisdiction. Lawsuit Commencement Date Trial commencement date We provide the expiration year on our rental equipment, not the complete date. Lease Expiration Year Lease expiration year The Life Insurance operating segment includes Oxford and its wholly-owned subsidiaries. Oxford provides life and health insurance products primarily to the senior market through the direct writing of life insurance. Medicare supplement and annuity policies. Life Insurance [Member] Life Insurance Loan date modification and extension of a revolving credit loan. Loan Modification and Extension Date Loan modification and extension date Date the counterclaim was filed by defendent. Loss Contingency Counterclaim Date Loss contingency counterclaim date The US-GAAP taxonomy only contains a single rate for related party transactions: RelatedPartyTransactionRate. We disclose a range of rates for management fees. Management Fees Rate, Highest Management fee rate, highest The latest maturity year for these debt instruments. Maturity End Year Debt instrument, maturity year range, end The earliest maturity year for these debt instruments. Maturity Start Year Debt instrument, maturity year range, start The DebtInstrumentMaturityDate could have worked for this element, but it must include the format Month-Date-Year. Will use this US-GAAP Element in the next few schedules, when possible, where we break down the various items that make up the Borrowing's narrative. Maturity Year Debt instrument, maturity year Mercury Partners, L.P. ("Mercury") owns and leases self-storage properties. Mercury [Member] Mercury Moving and Storage operations includes AMERCO, U-Haul and Real Estate and the wholly-owned subsidiaries of U-Haul and Real Estate. Operations consist of the rental of trucks and trailers, sales of moving supplies, sales of towing accessories, sales of propane, the rental of self-storage spaces to the "do-it-yourself" mover and management of self-storage properties owned by others. Operations are conducted under the registered trade name U-Haul(R) throughout the United States and Canada. Moving and Storage Consolidations [Member] Moving and Storage Operating Segment Paid-in-capital transfer of funds from company to related party Net Contribution from (to) Related Party Net contribution from (to) related party Aggregate notional amount on operating lease derivatives, which relates to the currency amount specified on operating lease derivatives. Notional Amount on Operating Lease Derivatives Notional amount of operating lease One time interest payment received on loans and other debt instruments. One Time Cash Interest Proceeds Received One time cash interest proceeds Several loans have a provision which allows the maturity date to be extended. The format we are using is 'PnYnMnD', for example the phrase '... option for a one year period...' would be defined with this value P1Y0M0D. Optional Extension Optional extension An investment program which issues U-Notes and does not go through underwriters or brokers. The U-Notes are backed by assets such as trailers, trucks, real estate and equipment. Other Borrowings [Member] U-Haul Investor Club List of other comprehensive income items not related to net earnings Other Comprehensive Income (Loss) [Abstract] Other comprehensive income (loss): Fair value of preferred stock at quoted prices in active markets. Preferred Stock, Fair Value Disclosure Preferred stock Listed separately the shares and values of common and preferred stock in treasury. Preferred Stock in Treasury [Member] Cost of preferred shares in treasury, net (6,100,000 shares as of June 30 and March 31, 2013) Cost of preferred shares in treasury, net Private Mini Storage Realty, L.P. (Private Mini") is ultimately controlled by Blackwater. Private Mini [Member] Private Mini Intercompany transactions between Amerco, U-Haul International and U-Haul Real Estate that are listed in the industry segmented Cash Flow Statement. Proceeds from (Repayment of) Intercompany Loans Proceeds from (repayment) of Intercompany loans Proceeds from (repayment of) intercompany loans The Property and Casualty Insurance operating segment includes RepWest and its wholly-owned subsidiaries and ARCOA risk retention group ("ARCOA"). Property and Casualty Insurance provides loss adjusting and claims handling for U-Haul through regional offices across North America. Property and Casualty Insurance also underwrites components of the Safemove, Safetow, Super Safemove and Safestor protection packages to U-Haul customers. The business plan for the Property and Casualty Insurance operating segment includes offering property and casualty products in other U-Haul related programs. ARCOA is a captive insurer owned by the Company whose purpose is to provide insurance products related to the moving and storage business. Property and Casualty Insurance [Member] Property and Casualty Insurance Purchase of equipment throughout a fiscal year. Purchase Equipment Through Fiscal Year Purchase equipment through fiscal year Quarter Ending [Abstract] Quarter ended: Amerco Real Estate Company and certain of its subsidiaries and U-Haul Company of Florida are borrowers under a Real Estate Loan. This portion of the loan is comprised of a term loan facility. This amortizing term portion requires monthly principal and interest payments, with the unpaid loan balance and accrued and unpaid interest due at maturity. The interest rate for the amortizing term portion, per the provisions of the amended Loan Agreement, is the applicable London Inter-Bank Offer Rate ("LIBOR") plus the applicable margin. U-Haul International, Inc. is the guarantor of the loan. Real Estate Loan, Amortizing Term, Loan One [Member] Real estate loan (amortizing term) [Member] Amerco Real Estate Company and U-Haul Company of Florida entered into a revolving credit agreement. The interest rate is the applicable LIBOR plus a margin. The default provisions of the loan include non-payment of principal or interest and other standard reporting and change-in-control covenants. AMERCO and U-Haul International, Inc. are guarantors of this facility. Real Estate Loan, Revolving Credit, Loan Two [Member] Real estate loan (revolving credit) [Member] Reclassification of Aoci To Earnings [Abstract] This extended concept is a combination of two concepts on the US-GAAP taxonomy. (1) Reinsurance Recoverables defined as..."The known and estimated amount recoverable as of the balance sheet date from reinsurers for claims paid or incurred by the ceding insurer and associated claims settlement expenses, including estimated amounts for claims incurred but not reported, and policy benefits, net of any related valuation allowance." (2) Receivables, Net, Current defined as..."The total amount due to the entity within one year of the balance sheet date (or one operating cycle, if longer) from outside sources, including trade accounts receivable, notes and loans receivable, as well as any other types of receivables, net of allowance established for the purpose of reducing such receivables to an amount that approximates their net realizable value" Reinsurance Recoverables and Trade Receivables, Net Reinsurance recoverables and trade receivables, net Related Party Cost and Expense [Abstract] Related party cost and expense: Related Party Notes Receivable [Abstract] Related party notes receivable: Related Party Revenue [Abstract] Related party transactions: The US-GAAP taxonomy only contains a single date for related party transactions. RelatedPartyTransaction Date. We disclose our earliest and latest maturities on the various outstanding notes only by the year. Related Party Transaction Date, Earliest Maturity Earliest maturity year The US-GAAP taxonomy only contains a single date for related party transactions. RelatedPartyTransaction Date. We disclose our earliest and latest maturities on the various outstanding notes only by the year. Related Party Transaction Date Latest Maturity Latest maturity year The US-GAAP taxonomy only contains a single rate for related party transactions: RelatedPartyTransactionRate. We disclose a range of rates for management fees. Related Party Transaction Rate, Lowest Management fee rate, lowest Rental Trucks and Rental Trailers and Other Rental Equipment are defined to be under the same US-GAAP concept, "Property subject to or available for operating lease, gross." The equipment is maintained so that our customers can complete a rental contract for a do-it-yourself move. Rental Trailers and Other Rental Equipment [Member] Rental trailers and other rental equipment The Amortizing Loans require monthly principal and interest payments, with the unpaid loan balance and accrued and unpaid interest due at maturity. These loans were used to purchase new trucks. The interest rate, per the provision of the Loan Agreements, are the applicable LIBOR plus a margin. Rental Truck Amortizing Credit First Loan [Member] Rental Truck (Amortizing Credit) First Loan [Member] The Amortizing Loans require monthly principal and interest payments, with the unpaid loan balance and accrued and unpaid interest due at maturity. These loans were used to purchase new trucks. The interest rate, per the provision of the Loan Agreements, are the applicable LIBOR plus a margin. Rental Truck Amortizing Credit Second Loan [Member] Rental Truck (Amortizing Credit) Second Loan [Member] The Amortizing Loans require monthly principal and interest payments, with the unpaid loan balance and accrued and unpaid interest due at maturity. These loans were used to purchase new trucks. The interest rate, per the provision of the Loan Agreements, are the applicable LIBOR plus a margin. Rental Truck Amortizing Credit Third Loan [Member] Rental Truck (Amortizing Credit) Third Loan [Member] Rental Trucks and Rental Trailers and Other Rental Equipment are defined to be under the same US-GAAP concept, "Property subject to or available for operating lease, gross." This equipment is maintained so that our customers can complete a rental contract for a do-it-yourself move. Rental Trucks [Member] Rental trucks Repwest provides property and casualty insurance to AMERCO and insures U-Haul customers, dealers and independent third parties. The majority of U-Haul customers purchase Repwest products. In addition, Repwest's business activities include direct and assumed reinsurance underwriting. Repwest [Member] Repwest The amount of revenue received excluding any revenue generated from dealer commissions or expenses as part of the dealer contract between the Company and these related party entities. Revenue Excluding Dealer Agreement Commissions and Expenses Revenue, excluding dealer agreement commissions and expenses Arrangement in which the loan proceeds can continuously be obtained following repayments, but the total amount borrowed cannot exceed a specified maximum amount. Revolving Fleet Loan One [Member] Revolving fleet loan one [Member] Debt arrangement having an initial term longer than one year or beyond the normal operating cycle with a provision to extend the life of the loan passed it's original maturity date. Revolving Fleet Loan Three [Member] Revolving fleet loan three [Member] Arrangement that allows loan proceeds to continuously be obtained following repayments, but the total amount borrowed cannot exceed a specified maximum amount. Revolving Fleet Loan Two [Member] Revolving fleet loan two [Member] Amerco has agreements and notes with these entities. Sac Holdings, Four Sac, Five Sac, Galaxy, and Private Mini [Member] SAC Holdings, Four SAC, Five SAC, Galaxy, and Private Mini This provides just the cost and expense for SAC holdings. Sac Holdings Lease and Rental Expense Expenses, related parties Substantially all of the equity interest in SAC Holdings is controlled by Blackwater investments, Inc. ("Blackwater"). Sac Holdings [Member] SAC Holdings Amerco manages the self-storage properties of these entities. Sac Holdings, Mercury, Four Sac, Five Sac, Galaxy and Private Mini [Member] SAC Holdings, Mercury, Four SAC, Five SAC, Galaxy and Private Mini Asset-backed note. Is a bankruptcy-remote special purpose entity wholly-owned by U-Haul International, Inc. The note is secured by new box truck purchases throughout fiscal 2008. U. S. Bank, NA acts as the trustee for this securitization. Securitization First Loan [Member] Securitization First Loan Asset-backed note. Is a bankruptcy-remote special purpose entity wholly-owned by U-Haul International, Inc. The note is secured by new box truck purchases. U.S. Bank, NA acts as the trustee for this securitization. Securitization Second Loan [Member] Securitization Second Loan This company-specific concept is a combination of two separate concepts in the US-GAAP taxonomy. (1) Other Real Estate Revenue: "Other real estate revenue not otherwise specified in the taxonomy." (2) Contracts Revenue: "Revenue earned during the period arising from products sold or services provided under the terms of a contract, not elsewhere specified in the taxonomy. May include government contracts, construction contracts, and any other contract related to a particular project or product. Self Storage Revenues Self-storage revenues Create a common stock member to incorporate the value shown in the heading of this section. Series Common Stock With or Without Par Value [Member] Series common stock, with or without par value, 150,000,000 shares authorized: This member further defines the concepts that follow. In this way, share concepts can be repeated and are unique to the taxonomy. Series Preferred Stock With or Without Par Value [Member] Series preferred stock, with or without par value, 50,000,000 shares authorized: AMERCO has been leasing equipment for several decades with no material losses relating to these types of residual value guarantees. This provides the original date when the Company started leasing. Started Leasing Equipment Date Started leasing equipment date Several subsidiary companies of U-Haul International associated with a term note for the purchase of cargo vans and pickups. Subsidiaries of Uhaul Intl [Member] Subsidiaries of U-Haul Int'l The amount of corporate (parent company) debt held by our insurance subsidiaries. Subsidiaries Share of Debt Purchased from Parent Subsidiary holdings of parent company debt On our HTML document, we leave this field name blank. It is considered the sum of all assets prior to our listing all Property, Plant and Equipment items. Subtotal Assets Subtotal assets Summary of Accumulated Other Comprehensive Income (Loss) Components, Net of Tax [Abstract] This is the seventh of sixteen active swap agreements. The Company manages exposure to changes in market interest rates. The Company's use of derivative instruments is limited to highly effective interest rate swaps to hedge the risk of changes in cash flows (future interest payments) attributable to changes in LIBOR swap rates, the designated benchmark interest rate being hedged on certain of our LIBOR indexed variables rate debt. The interest rate swaps effectively fix the Company's interest payments on certain LIBOR index variable rate debt. The Company monitors its positions and the credit ratings of its counterparties and does not currently anticipate non-performance by the counterparties. Interest rate swap agreements are not entered into for trading purposes. Swap Agreement Eight [Member] Swap Agreement Eight This is the tenth of sixteen active swap agreements. The Company manages exposure to changes in market interest rates. The Company's use of derivative instruments is limited to highly effective interest rate swaps to hedge the risk of changes in cash flows (future interest payments) attributable to changes in LIBOR swap rates, the designated benchmark interest rate being hedged on certain of our LIBOR indexed variables rate debt. The interest rate swaps effectively fix the Company's interest payments on certain LIBOR index variable rate debt. The Company monitors its positions and the credit ratings of its counterparties and does not currently anticipate non-performance by the counterparties. Interest rate swap agreements are not entered into for trading purposes. Swap Agreement Eleven [Member] Swap Agreement Eleven This is the fourteen of sixteen active swap agreements. The Company manages exposure to changes in market interest rates. The Company's use of derivative instruments is limited to highly effective interest rate swaps to hedge the risk of changes in cash flows (future interest payments) attributable to changes in LIBOR swap rates, the designated benchmark interest rate being hedged on certain of our LIBOR indexed variables rate debt. The interest rate swaps effectively fix the Company's interest payments on certain LIBOR index variable rate debt. The Company monitors its positions and the credit ratings of its counterparties and does not currently anticipate non-performance by the counterparties. Interest rate swap agreements are not entered into for trading purposes. Swap Agreement Fifteen [Member] Swap Agreement Fifteen This is the fourth of sixteen active swap agreements. The Company manages exposure to changes in market interest rates. The Company's use of derivative instruments is limited to highly effective interest rate swaps to hedge the risk of changes in cash flows (future interest payments) attributable to changes in LIBOR swap rates, the designated benchmark interest rate being hedged on certain of our LIBOR indexed variables rate debt. The interest rate swaps effectively fix the Company's interest payments on certain LIBOR index variable rate debt. The Company monitors its positions and the credit ratings of its counterparties and does not currently anticipate non-performance by the counterparties. Interest rate swap agreements are not entered into for trading purposes. Swap Agreement Five [Member] Swap Agreement Five This is the third of sixteen active swap agreements. The Company manages exposure to changes in market interest rates. The Company's use of derivative instruments is limited to highly effective interest rate swaps to hedge the risk of changes in cash flows (future interest payments) attributable to changes in LIBOR swap rates, the designated benchmark interest rate being hedged on certain of our LIBOR indexed variables rate debt. The interest rate swaps effectively fix the Company's interest payments on certain LIBOR index variable rate debt. The Company monitors its positions and the credit ratings of its counterparties and does not currently anticipate non-performance by the counterparties. Interest rate swap agreements are not entered into for trading purposes. Swap Agreement Four [Member] Swap Agreement Four This is the thirteen of sixteen active swap agreements. The Company manages exposure to changes in market interest rates. The Company's use of derivative instruments is limited to highly effective interest rate swaps to hedge the risk of changes in cash flows (future interest payments) attributable to changes in LIBOR swap rates, the designated benchmark interest rate being hedged on certain of our LIBOR indexed variables rate debt. The interest rate swaps effectively fix the Company's interest payments on certain LIBOR index variable rate debt. The Company monitors its positions and the credit ratings of its counterparties and does not currently anticipate non-performance by the counterparties. Interest rate swap agreements are not entered into for trading purposes. Swap Agreement Fourteen [Member] Swap Agreement Fourteen This is the eighth of sixteen active swap agreements. The Company manages exposure to changes in market interest rates. The Company 's use of derivative instruments is limited to highly effective interest rate swaps to hedge the risk of changes in cash flows (future interest payments) attributable to changes in LIBOR swap rates, the designated benchmark interest rate being hedged on certain of our LIBOR indexed variables rate debt. The interest rate swaps effectively fix the Company's interest payments on certain LIBOR index variable rate debt. The Company monitors its positions and the credit ratings of its counterparties and does not currently anticipate non-performance by the counterparties. Interest rate swap agreements are not entered into for trading purposes. Swap Agreement Nine [Member] Swap Agreement Nine This is the first of sixteen active swap agreements. The Company manages exposure to changes in market interest rates. The Company's use of derivative instruments is limited to highly effective interest rate swaps to hedge the risk of changes in cash flows (future interest payments) attributable to changes in LIBOR swap rates, the designated benchmark interest rate being hedged on certain of our LIBOR indexed variables rate debt. The interest rate swaps effectively fix the Company's interest payments on certain LIBOR index variable rate debt. The Company monitors its positions and the credit ratings of its counterparties and does not currently anticipate non-performance by the counterparties. Interest rate swap agreements are not entered into for trading purposes. Swap Agreement One [Member] Swap Agreement One This is the sixth of sixteen active swap agreements. The Company manages exposure to changes in market interest rates. The Company's use of derivative instruments is limited to highly effective interest rate swaps to hedge the risk of changes in cash flows (future interest payments) attributable to changes in LIBOR swap rates, the designated benchmark interest rate being hedged on certain of our LIBOR indexed variables rate debt. The interest rate swaps effectively fix the Company's interest payments on certain LIBOR index variable rate debt. The Company monitors its positions and the credit ratings of its counterparties and does not currently anticipate non-performance by the counterparties. Interest rate swap agreements are not entered into for trading purposes. Swap Agreement Seven [Member] Swap Agreement Seven This is the sixteen of sixteen active swap agreements. The Company manages exposure to changes in market interest rates. The Company's use of derivative instruments is limited to highly effective interest rate swaps to hedge the risk of changes in cash flows (future interest payments) attributable to changes in LIBOR swap rates, the designated benchmark interest rate being hedged on certain of our LIBOR indexed variables rate debt. The interest rate swaps effectively fix the Company's interest payments on certain LIBOR index variable rate debt. The Company monitors its positions and the credit ratings of its counterparties and does not currently anticipate non-performance by the counterparties. Interest rate swap agreements are not entered into for trading purposes. Swap Agreement Seventeen [Member] Swap Agreement Seventeen This is the fifth of sixteen active swap agreements. The Company manages exposure to changes in market interest rates. The Company's use of derivative instruments is limited to highly effective interest rate swaps to hedge the risk of changes in cash flows (future interest payments) attributable to changes in LIBOR swap rates, the designated benchmark interest rate being hedged on certain of our LIBOR indexed variables rate debt. The interest rate swaps effectively fix the Company's interest payments on certain LIBOR index variable rate debt. The Company monitors its positions and the credit ratings of its counterparties and does not currently anticipate non-performance by the counterparties. Interest rate swap agreements are not entered into for trading purposes. Swap Agreement Six [Member] Swap Agreement Six This is the fifteen of sixteen active swap agreements. The Company manages exposure to changes in market interest rates. The Company's use of derivative instruments is limited to highly effective interest rate swaps to hedge the risk of changes in cash flows (future interest payments) attributable to changes in LIBOR swap rates, the designated benchmark interest rate being hedged on certain of our LIBOR indexed variables rate debt. The interest rate swaps effectively fix the Company's interest payments on certain LIBOR index variable rate debt. The Company monitors its positions and the credit ratings of its counterparties and does not currently anticipate non-performance by the counterparties. Interest rate swap agreements are not entered into for trading purposes. Swap Agreement Sixteen [Member] Swap Agreement Sixteen This is the ninth of sixteen active swap agreements. The Company manages exposure to changes in market interest rates. The Company's use of derivative instruments is limited to highly effective interest rate swaps to hedge the risk of changes in cash flows (future interest payments) attributable to changes in LIBOR swap rates, the designated benchmark interest rate being hedged on certain of our LIBOR indexed variables rate debt. The interest rate swaps effectively fix the Company's interest payments on certain LIBOR index variable rate debt. The Company monitors its positions and the credit ratings of its counterparties and does not currently anticipate non-performance by the counterparties. Interest rate swap agreements are not entered into for trading purposes. Swap Agreement Ten [Member] Swap Agreement Ten This is the twelve of sixteen active swap agreements. The Company manages exposure to changes in market interest rates. The Company's use of derivative instruments is limited to highly effective interest rate swaps to hedge the risk of changes in cash flows (future interest payments) attributable to changes in LIBOR swap rates, the designated benchmark interest rate being hedged on certain of our LIBOR indexed variables rate debt. The interest rate swaps effectively fix the Company's interest payments on certain LIBOR index variable rate debt. The Company monitors its positions and the credit ratings of its counterparties and does not currently anticipate non-performance by the counterparties. Interest rate swap agreements are not entered into for trading purposes. Swap Agreement Thirteen [Member] Swap Agreement Thirteen This is the second of sixteen active swap agreements. The Company manages exposure to changes in market interest rates. The Company's use of derivative instruments is limited to highly effective interest rate swaps to hedge the risk of changes in cash flows (future interest payments) attributable to changes in LIBOR swap rates, the designated benchmark interest rate being hedged on certain of our LIBOR indexed variables rate debt. The interest rate swaps effectively fix the Company's interest payments on certain LIBOR index variable rate debt. The Company monitors its positions and the credit ratings of its counterparties and does not currently anticipate non-performance by the counterparties. Interest rate swap agreements are not entered into for trading purposes. Swap Agreement Three [Member] Swap Agreement Three This is the eleven of sixteen active swap agreements. The Company manages exposure to changes in market interest rates. The Company's use of derivative instruments is limited to highly effective interest rate swaps to hedge the risk of changes in cash flows (future interest payments) attributable to changes in LIBOR swap rates, the designated benchmark interest rate being hedged on certain of our LIBOR indexed variables rate debt. The interest rate swaps effectively fix the Company's interest payments on certain LIBOR index variable rate debt. The Company monitors its positions and the credit ratings of its counterparties and does not currently anticipate non-performance by the counterparties. Interest rate swap agreements are not entered into for trading purposes. Swap Agreement Twelve [Member] Swap Agreement Twelve Terms of the loan were amended on this date. Term Note Amended Date Term note amended date Timing difference for interecompany balances with insurance subsidiaries. The balance includes the redemption of our Preferred stock. Timing Difference Insurance Subsidiaries Others Other The taxonomy requires that CommonStockMember cannot have different Table/Axis/Domains. We were using this member in our Balance Sheet, Balance Sheet Parenthetical, Segment Balance Sheet, and an Available-for-Sale Investments table. The Available-for-Sale Investments table now is the only one using CommonStockMember. We've changed the other three Balance Sheet schedules to this extended stock concept to comply with the taxonomy rules. Uhaul Common Stock [Member] Common stock of $0.25 par value, 150,000,000 shares authorized; 41,985,700 issued and 19,607,788 outstanding as of June 30 and March 31, 2013 Common stock U-Haul International is the guarantor for certain loans. Uhaul Guarantor [Member] U-Haul Guarantor U-Haul International, North America's largest "do-it-yourself" moving and storage operator. Uhaul Intl, Amerco [Member] U-Haul Int'l and Amerco Guarantor [Member] Subsidiaries who are borrowers under amortizing term loans Uhaul Intl and Subsidiaries [Member] U-Haul Int'l and Subsidiaries U-Haul International, North America's largest "do-it-yourself" moving and storage operator. Uhaul [Member] U-Haul Borrowers of the U-Haul S Fleet ("2007 Box Truck Note") asset-backed note. Uhaul S Fleet Two Thousand and Seven Box Truck Note [Member] U-Haul S Fleet, 2007 Box Truck Note Borrowers of the U-Haul S Fleet ("2010 Box Truck Note") asset-backed note. Uhaul S Fleet Two Thousand Ten Box Truck Note [Member] U-Haul S Fleet, 2010 Box Truck Note The adjusted cost and estimated market value of available-for-sale investments by contractual maturity schedule requires a subtotal for the Due after... information (group 102010). In order to accomplish this, added this hierarchy to this group. Us Treasury, Government, and Corporate Securities [Member] U.S. treasury, government, and corporate securities Combination of subsidiary companies holds various junior unsecured notes due from SAC Holdings, a related party. Various Subsidiaries of Amerco [Member] Various Subsidiaries of Amerco Affiliates of Amerco with outstanding senior mortgage notes Various Subsidiaries of Amerco Real Estate and Uhaul Intl [Member] Various Subsidiaries of Amerco Real Estate and U-Haul Int'l Accounting Policies [Abstract] Accounts Payable and Accrued Liabilities Accounts payable and accrued expenses Accumulated Defined Benefit Plans Adjustment [Member] Postretirement Benefit Obligation Gain [Member] Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment Less: Accumulated depreciation Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges [Member] Fair Market Value of Cash Flow Hedges [Member] Accumulated Net Unrealized Investment Gain (Loss) [Member] Unrealized Net Gain on Investments [Member] Accumulated Other Comprehensive Income (Loss) [Line Items] Balance as of June 30, 2014 Balance as of March 31, 2014 Accumulated Other Comprehensive Income (Loss), Net of Tax Accumulated other comprehensive loss Accumulated Other Comprehensive Income (Loss) [Table] Accumulated Other Comprehensive Income (Loss) [Member] Accumulated Other Comprehensive Income (Loss) Accumulated Translation Adjustment [Member] Foreign Currency Translation [Member] Additional Paid in Capital Additional paid-in capital Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract] Adjustments to reconcile net earnings to cash provided by operations: Amortization of Debt Discount (Premium) Amortization of transaction costs Assets [Abstract] ASSETS: Assets: Assets, Fair Value Disclosure Total Assets Held by Insurance Regulators Assets held by insurance regulators Assets Identifiable assets Total assets Debt securities, amortized cost Available-for-sale Securities [Abstract] Available-for-sale securities, investments: Available-for-sale securities, fair value: Available-for-sale Securities, Amortized Cost Basis [Abstract] Available-for-sale securities, amortized cost: Amortized cost Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value Gross unrealized losses less than 12 months Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value Gross unrealized losses more than 12 months Available-for-sale Securities, Debt Maturities, Year Six Through Ten, Amortized Cost Basis Due after five years through ten years Available-for-sale Securities, Debt Maturities, Year Six Through Ten, Fair Value Due after five years through ten years Available-for-sale Securities, Debt Maturities, Year Two Through Five, Amortized Cost Basis Due after one year through five years Available-for-sale Securities, Debt Maturities, Year Two Through Five, Fair Value Due after one year through five years Available-for-sale Securities, Debt Maturities, after Ten Years, Amortized Cost Basis Due after ten years Available-for-sale Securities, Debt Maturities, after Ten Years, Fair Value Due after ten years Available-for-sale investments, Amortized cost, subtotal Debt securities, fair value Available-for-sale Securities, Debt Maturities, Next Twelve Months, Amortized Cost Basis Due in one year or less Available-for-sale Securities, Debt Maturities, Next Twelve Months, Fair Value Due in one year or less Available-for-sale investments, Amortized cost, total Available-for-sale investments, Estimated market value, total Available-for-sale investments, Estimated market value, subtotal Available-for-sale Securities, Gross Realized Gains (Losses), Sale Proceeds Fair value of sold available-for-sale securities Available-for-sale Securities, Gross Realized Gains Available-for-sale securities, gross realized gains Available-for-sale Securities, Gross Realized Losses Available-for-sale securities, gross realized losses Available-for-sale Securities [Table Text Block] Available-for-sale securities Available-for-Sale Investments Available-for-sale Securities Fixed maturities - available for sale Basis of Presentation and Significant Accounting Policies [Text Block] 1. Basis of Presentation Buildings and Improvements, Gross Buildings and improvements Capital Lease Obligations [Member] Capital Lease Obligations Cash and cash equivalents at the end of the period Cash and cash equivalents at the beginning of period Cash and Cash Equivalents, at Carrying Value Cash and cash equivalents Cash and Cash Equivalents, Period Increase (Decrease) Increase (decrease) in cash and cash equivalents Class of Stock [Domain] Commercial Loan [Member] Working capital loan (revolving credit) [Member]