Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
CURRENT ASSETS
Cash and cash equivalents	$ 105,019	$ 75,378
Trade receivables, net of allowance of $1.5 million and $1.5 million	61,571	64,293
Prepaid tires	11,045	10,989
Other current assets	21,923	13,782
Income tax receivable	9,691	6,393
Total current assets	209,249	170,835
PROPERTY AND EQUIPMENT
Land and land improvements	40,973	40,283
Buildings	49,957	48,657
Leasehold improvements	1,097	2,208
Furniture and fixtures	3,290	3,437
Shop and service equipment	12,904	12,202
Revenue equipment	550,193	555,980
Construction in progress	4,060	3,996
Property, Plant and Equipment, Gross	662,474	666,763
Less accumulated depreciation	223,331	223,901
Property and equipment, net	439,143	442,862
GOODWILL	132,410	132,410
OTHER INTANGIBLES, NET	16,352	17,022
Deferred Income Taxes, Net	3,237	1,737
OTHER ASSETS	22,825	24,261
Assets	823,216	789,127
CURRENT LIABILITIES
Accounts payable and accrued liabilities	38,771	14,366
Compensation and benefits	27,324	26,752
Insurance accruals	19,991	21,368
Other accruals	12,284	12,835
Total current liabilities	98,370	75,321
LONG-TERM LIABILITIES
Income taxes payable	6,124	8,147
Deferred income taxes, net	72,172	65,488
Insurance accruals less current portion	61,461	65,526
Total long-term liabilities	139,757	139,161
COMMITMENTS AND CONTINGENCIES (Note 15)
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 2018 and 2017; outstanding 83,240 in 2018 and 83,303 in 2017	907	907
Additional paid-in capital	3,414	3,518
Retained earnings	705,885	694,174
Treasury stock, at cost; 7,449 shares in 2018 and 7,386 in 2017	(125,117)	(123,954)
Stockholders' Equity Attributable to Parent	585,089	574,645
Liabilities and Stockholders' Equity	$ 823,216	$ 789,127