Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011
CURRENT ASSETS
Cash and cash equivalents	$ 212,741	$ 139,770
Trade receivables, net	50,756	44,198
Prepaid tires	7,146	12,820
Other current assets	4,550	1,932
Income tax receivable	1,828	314
Deferred income taxes, net	13,069	14,401
Total current assets	290,090	213,435
PROPERTY AND EQUIPMENT
Land and land improvements	17,451	17,451
Buildings	26,761	26,761
Furniture and fixtures	2,269	2,269
Shop and service equipment	7,268	7,324
Revenue equipment	356,519	355,905
Property, Plant and Equipment, Gross	410,268	409,710
Less accumulated depreciation	188,280	161,269
Property and equipment, net	221,988	248,441
LONG-TERM INVESTMENTS	21,041	50,569
GOODWILL	4,815	4,815
OTHER ASSETS	8,410	8,406
Assets	546,344	525,666
CURRENT LIABILITIES
Accounts payable and accrued liabilities	9,258	9,088
Compensation and benefits	16,928	15,493
Insurance accruals	13,916	13,997
Other accruals	7,384	7,085
Total current liabilities	47,486	45,663
LONG-TERM LIABILITIES
Income taxes payable	21,855	24,077
Deferred income taxes, net	47,263	57,661
Insurance accruals less current portion	57,582	57,494
Total long-term liabilities	126,700	139,232
COMMITMENTS AND CONTINGENCIES (Note 11)
STOCKHOLDERS' EQUITY
Preferred stock, par value $.01; authorized 5,000 shares; none issued	0	0
Capital stock, common, $.01 par value; authorized 395,000 shares; issued 90,689 in 2012 and 2011, outstanding, 85,490 in 2012 and 86,475 in 2011, respectively	907	907
Additional paid-in capital	2,589	589
Retained earnings	440,768	398,706
Treasury stock, at cost; 5,199 shares in 2012 and 4,214 in 2011	(70,822)	(56,350)
Accumulated other comprehensive loss	(1,284)	(3,081)
Stockholders' Equity Attributable to Parent	372,158	340,771
Liabilities and Stockholders' Equity	$ 546,344	$ 525,666