SEGMENTS - Reportable Segment Information (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Net sales
Total net sales	$ 642,769	$ 449,422	$ 1,189,530	$ 841,425
Income (loss) from operations	35,908	22,684	56,043	33,899
Transportation Solutions
Net sales
Total net sales	593,125	401,085	1,094,165	745,423
Parts & Services
Net sales
Total net sales	49,644	48,337	95,365	96,002
Corporate and Eliminations
Net sales
Total net sales	(3,608)	(1,507)	(5,620)	(3,218)
Income (loss) from operations	(20,203)	(12,192)	(38,554)	(23,984)
Corporate and Eliminations | Transportation Solutions
Net sales
Total net sales	2,857	1,092	3,882	1,873
Corporate and Eliminations | Parts & Services
Net sales
Total net sales	751	415	1,738	1,345
Operating Segments | Transportation Solutions
Net sales
Total net sales	595,982	402,177	1,098,047	747,296
Income (loss) from operations	47,973	26,815	79,670	43,438
Operating Segments | Parts & Services
Net sales
Total net sales	50,395	48,752	97,103	97,347
Income (loss) from operations	$ 8,138	$ 8,061	$ 14,927	$ 14,445