Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2021	Mar. 31, 2020
ASSETS:
Cash and cash equivalents	$ 1,194,012	$ 494,352
Reinsurance recoverables and trade receivables, net	224,426	186,672
Inventories, net	105,577	101,083
Prepaid expenses	469,144	562,904
Investments, fixed maturities and marketable equities	2,695,656	2,492,738
Investments, other	489,759	360,373
Deferred policy acquisition costs, net	89,749	103,118
Other assets	47,730	71,956
Right of use assets, financing, net	877,038	1,080,353
Right of use assets, operating	92,505	106,631
Related party assets	35,395	34,784
Subtotal assets	6,320,991	5,594,964
Property, plant and equipment, at cost:
Land	1,075,813	1,032,945
Buildings and improvements	5,163,705	4,663,461
Furniture and equipment	786,505	752,363
Property, plant and equipment (gross)	11,413,668	10,556,222
Less: Accumulated depreciation	(3,083,053)	(2,713,162)
Total property, plant and equipment	8,330,615	7,843,060
Total assets	14,651,606	13,438,024
Liabilities:
Accounts payable and accrued expenses	645,575	554,353
Notes, loans and leases payable	4,668,907	4,621,291
Operating lease liabilities	92,510	106,443
Policy benefits and losses, claims and loss expenses payable	997,701	997,647
Liabilities from investment contracts	2,161,530	1,802,217
Other policyholders' funds and liabilities	12,420	10,190
Deferred income	42,592	31,620
Deferred income taxes, net	1,178,489	1,093,543
Total liabilities	9,799,724	9,217,304
Commitments and contingencies (notes 9, 16, 17 and 18)
Stockholders' equity:
Additional paid-in capital	453,819	453,819
Accumulated other comprehensive loss	106,857	34,652
Retained earnings	4,958,359	4,399,402
Unearned employee stock ownership plan shares	0	0
Total stockholders' equity	4,851,882	4,220,720
Total liabilities and stockholders' equity	14,651,606	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
Series A 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	477,921	511,520
Rental Trucks [Member]
Property, plant and equipment, at cost:
Property subject to or available for operating lease, gross	$ 3,909,724	$ 3,595,933