Schedule II - Amerco and Consolidated Subsidiaries Valuation and Qualifying Accounts	12 Months Ended
	Mar. 31, 2021
Disclosure Text Block [Abstract]
Schedule Of Valuation And Qualifying Accounts Disclosure [Text Block]	SCHEDULE II AMERCO AND CONSOLIDATED SUBSIDIARIES VALUATION AND QUALIFYING ACCOUNTS       Balance at Beginning of Year   Additions Charged to Costs and Expenses   Additions Charged to Other Accounts   Deductions   Balance at Year End                       Year ended March 31, 2021   (In thousands) Allowance for doubtful accounts                     (deducted from trade receivable) $ 535 $ 2,179 $ 2,680 $ (973) $ 4,421 Allowance for obsolescence                     (deducted from inventory) $ 3,063 $ - $ - $ (1,647) $ 1,416 Allowance for LIFO                     (deducted from inventory) $ 18,886 $ 2,946 $ - $ - $ 21,832 Allowance for probable losses                     (deducted from mortgage loans) $ 493 $ - $ - $ (45) $ 448                       Year ended March 31, 2020     Allowance for doubtful accounts                     (deducted from trade receivable) $ 549 $ 731 $ - $ (745) $ 535 Allowance for obsolescence                     (deducted from inventory) $ 2,322 $ 741 $ - $ - $ 3,063 Allowance for LIFO                     (deducted from inventory) $ 18,987 $ - $ - $ (101) $ 18,886 Allowance for probable losses                     (deducted from mortgage loans) $ 493 $ - $ - $ - $ 493                       Year ended March 31, 2019                     Allowance for doubtful accounts                     (deducted from trade receivable) $ 496 $ 1,550 $ - $ (1,497) $ 549 Allowance for obsolescence                     (deducted from inventory) $ 5,329 $ - $ - $ (3,007) $ 2,322 Allowance for LIFO                     (deducted from inventory) $ 16,126 $ 2,861 $ - $ - $ 18,987 Allowance for probable losses                     (deducted from mortgage loans) $ 618 $ - $ - $ (125) $ 493