SEGMENT REPORTING - Segment Reporting Information by Segment (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Segment Reporting Information
Operating revenue	$ 202,130	$ 170,031	$ 403,193	$ 328,536
Operating income	5,852	6,929	24,535	12,975
Unallocated merger costs	2,132	0	2,132
Depreciation and amortization	8,986	9,163	17,010	18,733
Trucking
Segment Reporting Information
Operating revenue	122,404	105,102	238,433	207,878
USAT Logistics
Segment Reporting Information
Operating revenue	79,726	64,929	164,760	120,658
Operating Segments
Segment Reporting Information
Operating income	5,852	6,929	24,535	12,975
Unallocated merger costs	(2,132)		(2,132)
Depreciation and amortization	8,986	9,163	17,010	18,733
Operating Segments \| Trucking
Segment Reporting Information
Operating revenue	122,515	105,361	238,586	208,464
Operating income	4,296	3,057	16,925	6,577
Depreciation and amortization	8,576	8,901	16,296	18,197
Operating Segments \| USAT Logistics
Segment Reporting Information
Operating revenue	86,271	78,749	183,715	147,130
Operating income	3,688	3,872	9,742	6,398
Depreciation and amortization	410	262	714	536
Intersegment Eliminations
Segment Reporting Information
Operating revenue	(6,656)	(14,079)	(19,108)	(27,058)
Intersegment Eliminations \| Trucking
Segment Reporting Information
Operating revenue	(111)	(259)	(153)	(586)
Intersegment Eliminations \| USAT Logistics
Segment Reporting Information
Operating revenue	(6,545)	(13,820)	(18,955)	(26,472)
Foreign Countries \| Operating Segments \| Trucking
Segment Reporting Information
Operating revenue	$ 14,600	$ 10,000	$ 27,000	$ 18,900

This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

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