Accounting Policies, by Policy (Policies)	12 Months Ended
Dec. 31, 2014
Accounting Policies [Abstract]
New Accounting Pronouncements, Policy [Policy Text Block]	In the opinion of the management of USA Truck, Inc., the accompanying unaudited condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States (“GAAP”) for interim financial information. Certain information and footnote disclosures normally included in financial statements required by GAAP have been condensed or omitted. All normal recurring adjustments considered necessary for a fair presentation have been included. Operating results for the three months ended March 31, 2015, are not necessarily indicative of the results that may be expected for the year ending December 31, 2015. These financial statements should be read in conjunction with the financial statements, and footnotes thereto, included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2014.

Accounting Policies, by Policy (Policies)

12 Months Ended

Dec. 31, 2014

New Accounting Pronouncements, Policy [Policy Text Block]

In the opinion of the management of USA Truck, Inc., the accompanying unaudited condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States (“GAAP”) for interim financial information. Certain information and footnote disclosures normally included in financial statements required by GAAP have been condensed or omitted. All normal recurring adjustments considered necessary for a fair presentation have been included. Operating results for the three months ended March 31, 2015, are not necessarily indicative of the results that may be expected for the year ending December 31, 2015. These financial statements should be read in conjunction with the financial statements, and footnotes thereto, included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2014.