SEGMENT REPORTING - Segment Reporting Information by Segment (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Segment Reporting Information
Operating revenue	$ 130,924	$ 132,583	$ 398,520	$ 392,977
Operating income	(34)	5,803	5,870	12,506
Depreciation and amortization	9,652	6,735	27,595	21,392
Trucking
Segment Reporting Information
Operating revenue	93,354	85,529	283,963	249,831
USAT Logistics
Segment Reporting Information
Operating revenue	37,570	47,054	114,557	143,146
Operating Segments \| Trucking
Segment Reporting Information
Operating revenue	93,587	86,801	284,965	251,332
Operating income	(278)	2,605	2,168	4,294
Depreciation and amortization	9,435	6,562	26,867	20,887
Operating Segments \| USAT Logistics
Segment Reporting Information
Operating revenue	39,365	49,136	120,390	146,527
Operating income	244	3,198	3,702	8,212
Depreciation and amortization	217	173	728	505
Intersegment Eliminations
Segment Reporting Information
Operating revenue	(2,028)	(3,354)	(6,835)	(4,882)
Intersegment Eliminations \| Trucking
Segment Reporting Information
Operating revenue	(233)	(1,272)	(1,002)	(1,501)
Intersegment Eliminations \| USAT Logistics
Segment Reporting Information
Operating revenue	(1,795)	(2,082)	(5,833)	(3,381)
Foreign countries \| Operating Segments \| Trucking
Segment Reporting Information
Operating revenue	$ 9,500	$ 10,600	$ 28,500	$ 31,600

The current period expense charged against earnings on long-lived, physical assets not used in production, and which are not intended for resale, to allocate or recognize the cost of such assets over their useful lives; or to record the reduction in book value of an intangible asset over the benefit period of such asset; or to reflect consumption during the period of an asset that is not used in production.

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