Condensed Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Mar. 31, 2012
ASSETS:
Cash and cash equivalents	$ 586,124	$ 357,180
Reinsurance recoverables and trade receivables, net	226,340	297,974
Inventories, net	55,989	58,735
Prepaid expenses	55,148	41,858
Investments, fixed maturities and marketable equities	1,019,968	766,792
Investments, other	270,191	258,551
Deferred policy acquisition costs, net	93,533	63,914
Other assets	101,889	120,525
Related party assets	175,175	316,157
Subtotal assets	2,584,357	2,281,686
Property, plant and equipment, at cost:
Land	338,598	281,140
Buildings and improvements	1,155,754	1,087,119
Furniture and equipment	316,772	308,120
Property, plant and equipment (gross)	4,159,142	3,787,822
Less: Accumulated depreciation	(1,524,194)	(1,415,457)
Total property, plant and equipment	2,634,948	2,372,365
Total assets	5,219,305	4,654,051
Liabilities:
Accounts payable and accrued expenses	326,182	335,326
Notes, loans and leases payable	1,667,008	1,486,211
Policy benefits and losses, claims and loss expenses payable	1,115,823	1,145,943
Liabilities from investment contracts	486,502	240,961
Other policyholders' funds and liabilities	6,348	7,273
Deferred income	27,840	31,525
Deferred income taxes	399,103	370,992
Total liabilities	4,028,806	3,618,231
Commitments and contingencies (notes 4, 8, 9 and 10)
Stockholders' equity:
Additional paid-in capital	436,926	433,743
Accumulated other comprehensive loss	(22,192)	(45,436)
Retained earnings	1,444,757	1,317,064
Unearned employee stock ownership plan shares	(1,839)	(2,398)
Total stockholders' equity	1,190,499	1,035,820
Total liabilities and stockholders' equity	5,219,305	4,654,051
Series A preferred stock, with no par value, 6,100,000 authorized; 6,100,000 shares issued and none outstanding as of December 31 and March 31, 2012
Stockholders' equity:
Preferred stock, value, issued
Series B preferred stock, with no par value, 100,000 shares authorized; none issued and outstanding as of December 31 and March 31, 2012
Stockholders' equity:
Preferred stock, value, issued
Series A common stock of $0.25 par value, 10,000,000 shares authorized; none issued and outstanding as of December 31 and March 31, 2012
Stockholders' equity:
Common stock, value, issued
Common stock of $0.25 par value, 150,000,000 shares authorized; 41,985,700 issued and 19,607,788 outstanding as of December 31 and March 31, 2012
Stockholders' equity:
Common stock, value, issued	10,497	10,497
Cost of common shares in treasury, net (22,377,912 shares as of December 31 and March 31, 2012)
Stockholders' equity:
Treasury stock, value	(525,653)	(525,653)
Cost of preferred shares in treasury, net (6,100,000 shares as of December 31 and March 31, 2012)
Stockholders' equity:
Treasury stock, value	(151,997)	(151,997)
Rental trailers and other rental equipment
Property, plant and equipment, at cost:
Property subject to or available for operating lease, gross	303,379	255,010
Rental trucks
Property, plant and equipment, at cost:
Property subject to or available for operating lease, gross	$ 2,044,639	$ 1,856,433