Segment Reporting Information by Segment (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Segment Reporting Information [Line Items]
Operating revenue	$ 133,622	$ 135,381	$ 267,596	$ 260,394
Operating loss	1,983	4,311	5,904	6,703
Depreciation and amortization	9,125	7,477	17,943	14,657
Intersegment Eliminations
Segment Reporting Information [Line Items]
Operating revenue	(2,429)	(920)	(4,807)	(1,528)
Trucking
Segment Reporting Information [Line Items]
Operating revenue	96,069	85,569	190,609	164,302
Operating loss	837	2,153	2,445	1,689
Depreciation and amortization	8,853	7,299	17,432	14,325
Trucking \| Operating Segments
Segment Reporting Information [Line Items]
Operating revenue	96,476	85,685	191,378	164,531
Trucking \| Intersegment Eliminations
Segment Reporting Information [Line Items]
Operating revenue	(407)	(116)	(769)	(229)
USAT Logistics
Segment Reporting Information [Line Items]
Operating revenue	37,553	49,812	76,987	96,092
Operating loss	1,146	2,158	3,459	5,014
Depreciation and amortization	272	178	511	332
USAT Logistics \| Operating Segments
Segment Reporting Information [Line Items]
Operating revenue	39,575	50,616	81,025	97,391
USAT Logistics \| Intersegment Eliminations
Segment Reporting Information [Line Items]
Operating revenue	(2,022)	(804)	(4,038)	(1,299)
Foreign Countries \| Trucking \| Operating Segments
Segment Reporting Information [Line Items]
Operating revenue	$ 9,400	$ 11,000	$ 19,000	$ 20,900

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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