GOODWILL AND INTANGIBLE ASSETS - Schedule of Goodwill by Segment (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Increase (Decrease) in Goodwill [Roll Forward]
Beginning balance	$ 132,717	$ 74,618
Purchase accounting adjustments	(3,613)	(214)
Ending balance	129,104	132,717
ReedTMS
Increase (Decrease) in Goodwill [Roll Forward]
Beginning balance	52,841
Goodwill recorded in acquisition		52,841
Purchase accounting adjustments	(3,613)
Ending balance	49,228	52,841
Baylor
Increase (Decrease) in Goodwill [Roll Forward]
Goodwill recorded in acquisition		5,472
TTS
Increase (Decrease) in Goodwill [Roll Forward]
Beginning balance	53,897	38,084
Purchase accounting adjustments	(7,841)	0
Ending balance	46,056	53,897
TTS | ReedTMS
Increase (Decrease) in Goodwill [Roll Forward]
Goodwill recorded in acquisition		10,341
TTS | Baylor
Increase (Decrease) in Goodwill [Roll Forward]
Goodwill recorded in acquisition		5,472
Werner Logistics
Increase (Decrease) in Goodwill [Roll Forward]
Beginning balance	78,820	36,534
Purchase accounting adjustments	4,228	(214)
Ending balance	$ 83,048	78,820
Werner Logistics | ReedTMS
Increase (Decrease) in Goodwill [Roll Forward]
Goodwill recorded in acquisition		42,500
Werner Logistics | Baylor
Increase (Decrease) in Goodwill [Roll Forward]
Goodwill recorded in acquisition		$ 0