Consolidated Statements of Operations (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Revenues
Freight revenue	$ 538,933	$ 527,435	$ 512,026
Fuel surcharge revenue	145,616	146,819	140,601
Total revenue	684,549	674,254	652,627
Operating expenses:
Salaries, wages, and related expenses	218,946	217,080	211,169
Fuel expense	186,002	194,841	208,693
Operations and maintenance	50,043	45,839	43,862
Revenue equipment rentals and purchased transportation	102,954	85,010	63,353
Operating taxes and licenses	10,969	11,043	12,148
Insurance and claims	30,305	33,133	35,886
Communications and utilities	5,240	4,809	5,137
General supplies and expenses	16,002	16,068	15,627
Depreciation and amortization, including gains and losses on disposition of equipment	43,694	43,222	46,274
Goodwill impairment			11,539
Total operating expenses	664,155	651,045	653,688
Operating income (loss)	20,394	23,209	(1,061)
Other expenses (income):
Interest expense	10,400	12,697	16,208
Interest income			(32)
Other	(3)	(13)	(123)
Other expenses, net	10,397	12,684	16,053
Equity in income of affiliate	2,750	1,875	675
Income (loss) before income taxes	12,747	12,400	(16,439)
Income tax expense (benefit)	7,503	6,335	(2,172)
Net income (loss)	$ 5,244	$ 6,065	$ (14,267)
Income (loss) per share:
Basic income (loss) per share: (in Dollars per share)	$ 0.35	$ 0.41	$ (0.97)
Diluted income (loss) per share: (in Dollars per share)	$ 0.35	$ 0.41	$ (0.97)
Basic weighted average shares outstanding (in Shares)	14,837	14,742	14,689
Diluted weighted average shares outstanding (in Shares)	15,039	14,808	14,689