Segment Reporting Information by Segment (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Segment Reporting Information [Line Items]
Revenues	$ 132,583	$ 114,235	$ 392,977	$ 323,263
Operating loss	5,803	1,804	12,506	(7,561)
Depreciation and amortization	6,735	6,790	21,392	21,313
Trucking
Segment Reporting Information [Line Items]
Revenues	85,529	76,450	249,831	218,275
Trucking \| Operating Segments
Segment Reporting Information [Line Items]
Revenues	86,801	76,811	251,332	219,013
Operating loss	2,605	(1,194)	4,294	(13,165)
Depreciation and amortization	6,562	6,659	20,887	20,982
Trucking \| Intersegment Eliminations
Segment Reporting Information [Line Items]
Revenues	(1,272)	(361)	(1,501)	(738)
USAT Logistics
Segment Reporting Information [Line Items]
Revenues	47,054	37,785	143,146	104,988
USAT Logistics \| Operating Segments
Segment Reporting Information [Line Items]
Revenues	49,136	41,907	146,527	111,435
Operating loss	3,198	2,998	8,212	5,604
Depreciation and amortization	173	131	505	331
USAT Logistics \| Intersegment Eliminations
Segment Reporting Information [Line Items]
Revenues	$ (2,082)	$ (4,122)	$ (3,381)	$ (6,447)

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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