Consolidated Condensed Statements of Operations (Unaudited) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011
OPERATING REVENUE	$ 151,474	$ 137,856
OPERATING EXPENSES (INCOME):
Salaries, wages and benefits	38,271	34,099
Purchased transportation	29,859	28,017
Fuel and fuel taxes	39,124	35,340
Supplies and maintenance	9,536	9,662
Depreciation	14,535	13,516
Operating taxes and licenses	1,582	1,417
Insurance and claims	5,822	4,301
Communications and utilities	1,211	1,122
Gain on disposition of revenue equipment	(1,525)	(768)
Other	3,540	3,541
Total operating expenses	141,955	130,247
OPERATING INCOME	9,519	7,609
NET INTEREST (INCOME) EXPENSE	(21)	19
INCOME BEFORE INCOME TAXES	9,540	7,590
Less: Income before income taxes attributable to noncontrolling interest	161	137
INCOME BEFORE INCOME TAXES ATTRIBUTABLE TO MARTEN TRANSPORT, LTD.	9,379	7,453
PROVISION FOR INCOME TAXES	3,933	3,358
NET INCOME	$ 5,446	$ 4,095
BASIC EARNINGS PER COMMON SHARE (in Dollars per share)	$ 0.25	$ 0.19
DILUTED EARNINGS PER COMMON SHARE (in Dollars per share)	$ 0.25	$ 0.19
DIVIDENDS PAID PER COMMON SHARE (in Dollars per share)	$ 0.02	$ 0.02