Condensed Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
Current assets:
Cash and cash equivalents	$ 9,054	$ 6,846
Accounts receivable, net of allowance of $1,591 in 2013 and $1,729 in 2012	77,861	76,220
Drivers' advances and other receivables, net of allowance of $1,238 in 2013 and $1,041 in 2012	5,278	3,851
Inventory and supplies	4,670	4,550
Prepaid expenses	11,140	8,244
Assets held for sale	4,018	3,898
Deferred income taxes	5,015	4,642
Income taxes receivable	85	59
Total current assets	117,121	108,310
Property and equipment, at cost	417,965	419,947
Less: accumulated depreciation and amortization	(139,197)	(140,930)
Net property and equipment	278,768	279,017
Other assets, net	20,582	12,905
Total assets	416,471	400,232
Current liabilities:
Checks outstanding in excess of bank balances	7,782	8,261
Accounts payable	10,887	10,035
Accrued expenses	26,828	27,884
Current maturities of long-term debt	44,395	63,636
Current portion of capital lease obligations	2,164	2,091
Current portion of insurance and claims accrual	17,195	16,383
Total current liabilities	109,251	128,290
Long-term debt	122,810	95,214
Long-term portion of capital lease obligations	12,902	14,003
Insurance and claims accrual	23,892	16,768
Deferred income taxes	51,674	49,837
Other long-term liabilities	2,760	1,447
Total liabilities	323,289	305,559
Stockholders' equity:
Additional paid-in-capital	88,856	90,328
Treasury stock at cost; 955,605 shares and 1,059,643 shares as of June 30, 2013 and December 31, 2012, respectively	(12,786)	(13,955)
Accumulated other comprehensive income (loss)	(801)	320
Retained earnings	17,745	17,813
Total stockholders' equity	93,182	94,673
Total liabilities and stockholders' equity	416,471	400,232
Common Class A [Member]
Stockholders' equity:
Common stock	144	143
Common Class B [Member]
Stockholders' equity:
Common stock	$ 24	$ 24