Consolidated Condensed Balance Sheets (Unaudited) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Current assets:
Cash and cash equivalents	$ 9,041	$ 3,473
Receivables:
Trade, net	65,990	66,239
Other	5,388	7,177
Prepaid expenses and other	13,466	15,490
Deferred income taxes	3,260	3,155
Total current assets	97,145	95,534
Revenue equipment, buildings and land, office equipment and other	560,017	551,136
Accumulated depreciation	(152,071)	(156,660)
Net property and equipment	407,946	394,476
Other assets	3,206	613
TOTAL ASSETS	508,297	490,623
Current liabilities:
Accounts payable and accrued liabilities	47,718	33,062
Insurance and claims accruals	13,588	13,838
Total current liabilities	61,306	46,900
Long-term debt, less current maturities		2,726
Deferred income taxes	110,743	109,074
Total liabilities	172,049	158,700
Preferred stock, $.01 par value per share; 2,000,000 shares authorized; no shares issued and outstanding
Common stock, $.01 par value per share; 48,000,000 shares authorized; 22,121,505 shares at March 31, 2013, and 22,109,619 shares at December 31, 2012, issued and outstanding	221	221
Additional paid-in capital	82,918	82,679
Retained earnings	253,109	246,460
Total Marten Transport, Ltd. stockholders’ equity	336,248	329,360
Noncontrolling interest		2,563
Total stockholders’ equity	336,248	331,923
TOTAL LIABILITIES AND STOCKHOLDERS’ EQUITY	$ 508,297	$ 490,623