Consolidated Statements of Comprehensive Income (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Operating Revenue	$ 139,710	$ 137,192	$ 274,543	$ 264,884
Operating Expenses
Salaries, wages, and benefits	42,962	41,728	84,958	83,929
Rent and purchased transportation	1,596	1,998	3,257	3,936
Fuel	41,111	42,308	83,816	81,455
Operations and maintenance	6,251	6,150	11,903	11,246
Operating taxes and licenses	2,248	2,244	4,323	4,552
Insurance and claims	3,952	3,958	6,466	6,452
Communications and utilities	746	728	1,493	1,371
Depreciation	13,995	13,664	27,934	26,042
Other operating expenses	3,647	3,389	7,626	6,872
Gain on disposal of property and equipment	(3,546)	(11,662)	(7,760)	(15,530)
Total operating expenses	112,962	104,505	224,016	210,325
Operating income	26,748	32,687	50,527	54,559
Interest income	167	208	309	446
Income before income taxes	26,915	32,895	50,836	55,005
Federal and state income taxes	8,688	10,363	16,020	17,593
Net income	18,227	22,532	34,816	37,412
Other comprehensive income	1,797	0	1,797	0
Comprehensive Income	$ 20,024	$ 22,532	$ 36,613	$ 37,412
Earnings per share
Basic	$ 0.21	$ 0.25	$ 0.40	$ 0.41
Diluted	$ 0.21	$ 0.25	$ 0.40	$ 0.41
Weighted average shares outstanding
Basic	86,451	90,689	86,463	90,689
Diluted	86,779	90,689	86,802	90,689
Dividends declared per share	$ 0.02	$ 0.02	$ 0.04	$ 0.04