Segment Reporting - Summary of Company's Reportable Segment Information (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Segment Reporting Information [Line Items]
Revenues	$ 1,750,980	$ 1,391,083	$ 1,511,998
Income from operations	102,960	80,359	65,380
Depreciation and amortization	67,537	74,141	74,765
Operating Segments [Member] \| Contract Logistics [Member]
Segment Reporting Information [Line Items]
Revenues	627,220	459,666	515,185
Income from operations	44,809	35,967	48,376
Depreciation and amortization	33,504	32,386	33,670
Operating Segments [Member] \| Intermodal [Member]
Segment Reporting Information [Line Items]
Revenues	473,059	393,633	390,299
Income from operations	30,379	30,353	39,196
Depreciation and amortization	26,074	30,457	32,025
Operating Segments [Member] \| Trucking [Member]
Segment Reporting Information [Line Items]
Revenues	403,312	318,385	389,629
Income from operations	19,607	16,413	(21,485)
Depreciation and amortization	5,979	9,259	6,795
Operating Segments [Member] \| Company-managed Brokerage [Member]
Segment Reporting Information [Line Items]
Revenues	242,794	218,123	215,750
Income from operations	7,122	(2,681)	1,833
Depreciation and amortization	379	444	419
Other [Member]
Segment Reporting Information [Line Items]
Revenues	4,595	1,276	1,135
Income from operations	1,043	307	(2,540)
Depreciation and amortization	1,601	1,595	1,856
Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Revenues	(22,154)	(15,561)	(5,515)
Intersegment Eliminations [Member] \| Contract Logistics [Member]
Segment Reporting Information [Line Items]
Revenues	(530)	(1,962)	(835)
Intersegment Eliminations [Member] \| Intermodal [Member]
Segment Reporting Information [Line Items]
Revenues	(6,949)	(3,952)	(1,028)
Intersegment Eliminations [Member] \| Trucking [Member]
Segment Reporting Information [Line Items]
Revenues	(12,311)	(7,605)	(1,703)
Intersegment Eliminations [Member] \| Company-managed Brokerage [Member]
Segment Reporting Information [Line Items]
Revenues	$ (2,364)	$ (2,042)	$ (1,949)

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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