SEGMENTS - Reportable Segment Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Net sales
Total net sales	$ 546,761	$ 392,003
Income (loss) from operations	20,135	11,215
Transportation Solutions
Net sales
Total net sales	501,040	344,338
Parts & Services
Net sales
Total net sales	45,721	47,665
Corporate and Eliminations
Net sales
Total net sales	(2,012)	(1,711)
Income (loss) from operations	(18,351)	(11,792)
Corporate and Eliminations | Transportation Solutions
Net sales
Total net sales	1,025	781
Corporate and Eliminations | Parts & Services
Net sales
Total net sales	987	930
Operating Segments | Transportation Solutions
Net sales
Total net sales	502,065	345,119
Income (loss) from operations	31,697	16,623
Operating Segments | Parts & Services
Net sales
Total net sales	46,708	48,595
Income (loss) from operations	$ 6,789	$ 6,384