Consolidated Condensed Statements of Operations (Unaudited) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
OPERATING REVENUE	$ 168,423	$ 161,413	$ 327,832	$ 325,887
OPERATING EXPENSES (INCOME):
Salaries, wages and benefits	44,667	42,345	88,399	84,470
Purchased transportation	30,739	28,129	58,869	62,313
Fuel and fuel taxes	40,494	40,596	80,320	80,919
Supplies and maintenance	10,351	9,998	20,786	19,531
Depreciation	16,865	16,219	33,236	31,907
Operating taxes and licenses	1,728	1,825	3,441	3,595
Insurance and claims	6,663	5,808	12,788	11,619
Communications and utilities	1,311	1,262	2,744	2,545
Gain on disposition of revenue equipment	(1,278)	(1,237)	(1,941)	(3,652)
Other	3,951	3,347	7,618	6,981
Total operating expenses	155,491	148,292	306,260	300,228
OPERATING INCOME	12,932	13,121	21,572	25,659
OTHER	(612)	(153)	(710)	(168)
INCOME BEFORE INCOME TAXES	13,544	13,274	22,282	25,827
Less: Income before income taxes attributable to noncontrolling interest				84
INCOME BEFORE INCOME TAXES ATTRIBUTABLE TO MARTEN TRANSPORT, LTD.	13,544	13,274	22,282	25,743
PROVISION FOR INCOME TAXES	5,618	5,607	9,069	10,874
NET INCOME	$ 7,926	$ 7,667	$ 13,213	$ 14,869
BASIC EARNINGS PER COMMON SHARE (in Dollars per share)	$ 0.24	$ 0.23	$ 0.40	$ 0.45
DILUTED EARNINGS PER COMMON SHARE (in Dollars per share)	$ 0.24	$ 0.23	$ 0.39	$ 0.45
DIVIDENDS DECLARED PER COMMON SHARE (in Dollars per share)	$ 0.025	$ 0.017	$ 0.050	$ 0.033