Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2020	Mar. 31, 2020
ASSETS:
Cash and cash equivalents	$ 1,398,840	$ 494,352
Reinsurance recoverables and trade receivables, net	224,447	186,672
Inventories, net	104,180	101,083
Prepaid expenses	450,889	562,904
Investments, fixed maturities and marketable equities	2,606,953	2,492,738
Investments, other	447,902	360,373
Deferred policy acquisition costs, net	92,139	103,118
Other assets	44,261	71,956
Right of use Assets - Financing	920,321	1,080,353
Right of use Assets - Operating	97,186	106,631
Related party assets	34,963	34,784
Subtotal assets	6,422,081	5,594,964
Property, plant and equipment, at cost:
Land	1,059,177	1,032,945
Buildings and improvements	4,996,900	4,663,461
Furniture and equipment	778,732	752,363
Property, plant and equipment (gross)	11,017,589	10,556,222
Less: Accumulated depreciation	(2,992,365)	(2,713,162)
Total property, plant and equipment	8,025,224	7,843,060
Total assets	14,447,305	13,438,024
Liabilities:
Accounts payable and accrued expenses	608,765	554,353
Notes, loans and leases payable	4,678,227	4,621,291
Financing lease liability	561,351
Operating lease liability	97,224	106,443
Policy benefits and losses, claims and loss expenses payable	1,013,582	997,647
Liabilities from investment contracts	1,997,936	1,802,217
Other policyholders' funds and liabilities	34,867	10,190
Deferred income	37,005	31,620
Deferred income taxes, net	1,222,544	1,093,543
Total liabilities	9,690,150	9,217,304
Commitments and contingencies (notes 4, 8 and 9)
Stockholders' equity:
Additional paid-in capital	453,819	453,819
Accumulated other comprehensive loss	85,910	34,652
Retained earnings	4,884,579	4,399,402
Unearned employee stock ownership plan shares	0	0
Total stockholders' equity	4,757,155	4,220,720
Total liabilities and stockholders' equity	14,447,305	13,438,024
Series A Preferred Stock [Member]
Stockholders' equity:
Preferred stock, value, issued	0	0
Series B Preferred Stock [Member]
Stockholders' equity:
Preferred stock, value, issued	0	0
Serial Common Stock [Member]
Stockholders' equity:
Common stock, value, issued	0	0
Amerco Common Stock [Member]
Stockholders' equity:
Common stock, value, issued	10,497	10,497
Common Stock in Treasury [Member]
Stockholders' equity:
Treasury stock, value	(525,653)	(525,653)
Preferred Stock in Treasury [Member]
Stockholders' equity:
Treasury stock, value	(151,997)	(151,997)
Rental Trailers and Other Rental Equipment [Member]
Property, plant and equipment, at cost:
Property subject to or available for operating lease, gross	552,892	511,520
Rental Trucks [Member]
Property, plant and equipment, at cost:
Property subject to or available for operating lease, gross	$ 3,629,888	$ 3,595,933