Consolidated Statements of Operations (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Operating revenue	$ 603,679	$ 516,920	$ 505,874
Operating expenses (income):
Salaries, wages and benefits	147,646	131,519	138,752
Purchased transportation	120,332	110,408	106,577
Fuel and fuel taxes	155,595	114,927	99,898
Supplies and maintenance	40,311	35,218	38,223
Depreciation	57,531	51,916	53,069
Operating taxes and licenses	6,373	6,222	6,672
Insurance and claims	18,170	16,573	19,896
Communications and utilities	4,605	3,964	4,170
Gain on disposition of revenue equipment	(3,800)	(1,110)	(1,630)
Other	13,886	11,994	10,888
	560,649	481,631	476,515
Operating income	43,030	35,289	29,359
Net interest (income) expense	(24)	(26)	32
Income before income taxes	43,054	35,315	29,327
Less: Income before income taxes attributable to noncontrolling interest	807	631	584
Income before income taxes attributable to Marten Transport, Ltd.	42,247	34,684	28,743
Provision for income taxes	17,962	14,942	12,476
Net income	$ 24,285	$ 19,742	$ 16,267
Basic earnings per common share (in Dollars per share)	$ 1.10	$ 0.90	$ 0.74
Diluted earnings per common share (in Dollars per share)	$ 1.10	$ 0.90	$ 0.74
Dividends paid per common share (in Dollars per share)	$ 0.08	$ 0.04