SEGMENTS - Major Product Categories and Percentage of Consolidated Net Sales (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Product Information [Line Items]
Net sales	$ 642,769	$ 449,422	$ 1,189,530	$ 841,425
Sales Revenue, Net \| Product Concentration Risk
Product Information [Line Items]
Percentage of consolidated net sales	100.00%	100.00%	100.00%	100.00%
Eliminations
Product Information [Line Items]
Net sales	$ (3,608)	$ (1,507)	$ (5,620)	$ (3,218)
Transportation Solutions
Product Information [Line Items]
Net sales	593,125	401,085	1,094,165	745,423
Transportation Solutions \| Operating Segments
Product Information [Line Items]
Net sales	595,982	402,177	1,098,047	747,296
Transportation Solutions \| Eliminations
Product Information [Line Items]
Net sales	2,857	1,092	3,882	1,873
Parts & Services
Product Information [Line Items]
Net sales	49,644	48,337	95,365	96,002
Parts & Services \| Operating Segments
Product Information [Line Items]
Net sales	50,395	48,752	97,103	97,347
Parts & Services \| Eliminations
Product Information [Line Items]
Net sales	751	415	1,738	1,345
New trailers
Product Information [Line Items]
Net sales	$ 508,257	$ 321,833	$ 945,963	$ 590,763
New trailers \| Sales Revenue, Net \| Product Concentration Risk
Product Information [Line Items]
Percentage of consolidated net sales	79.10%	71.60%	79.50%	70.20%
New trailers \| Eliminations
Product Information [Line Items]
Net sales	$ (361)	$ 0	$ (672)	$ 0
New trailers \| Transportation Solutions \| Operating Segments
Product Information [Line Items]
Net sales	508,430	321,833	946,393	590,763
New trailers \| Parts & Services \| Operating Segments
Product Information [Line Items]
Net sales	188	0	242	0
Used trailers
Product Information [Line Items]
Net sales	$ 1,120	$ 378	$ 1,689	$ 1,390
Used trailers \| Sales Revenue, Net \| Product Concentration Risk
Product Information [Line Items]
Percentage of consolidated net sales	0.20%	0.10%	0.10%	0.20%
Used trailers \| Eliminations
Product Information [Line Items]
Net sales	$ 0	$ 0	$ 0	$ 0
Used trailers \| Transportation Solutions \| Operating Segments
Product Information [Line Items]
Net sales	0	0	0	165
Used trailers \| Parts & Services \| Operating Segments
Product Information [Line Items]
Net sales	1,120	378	1,689	1,225
Components, parts and services
Product Information [Line Items]
Net sales	$ 37,473	$ 34,260	$ 71,037	$ 26,362
Components, parts and services \| Sales Revenue, Net \| Product Concentration Risk
Product Information [Line Items]
Percentage of consolidated net sales	5.80%	7.60%	6.00%	3.10%
Components, parts and services \| Eliminations
Product Information [Line Items]
Net sales	$ 0	$ 0	$ 0	$ 0
Components, parts and services \| Transportation Solutions \| Operating Segments
Product Information [Line Items]
Net sales	0	0	0	0
Components, parts and services \| Parts & Services \| Operating Segments
Product Information [Line Items]
Net sales	37,473	34,260	71,037	26,362
Equipment and other
Product Information [Line Items]
Net sales	$ 95,919	$ 92,951	$ 170,841	$ 222,910
Equipment and other \| Sales Revenue, Net \| Product Concentration Risk
Product Information [Line Items]
Percentage of consolidated net sales	14.90%	20.70%	14.40%	26.50%
Equipment and other \| Eliminations
Product Information [Line Items]
Net sales	$ (3,247)	$ (1,507)	$ (4,948)	$ (3,218)
Equipment and other \| Transportation Solutions \| Operating Segments
Product Information [Line Items]
Net sales	87,552	80,344	151,654	156,368
Equipment and other \| Parts & Services \| Operating Segments
Product Information [Line Items]
Net sales	$ 11,614	$ 14,114	$ 24,135	$ 69,760