REVENUE - Disaggregation of Revenue by Revenue Source (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Disaggregation of revenue
Revenues	$ 3,289,978	$ 2,734,372	$ 2,372,178
Inter-segment eliminations
Disaggregation of revenue
Revenues	(5,218)	(899)	(107)
Truckload Transportation Services
Disaggregation of revenue
Revenues	2,428,686	2,045,073	1,843,209
Werner Logistics
Disaggregation of revenue
Revenues	793,492	622,461	469,791
Transportation services
Disaggregation of revenue
Revenues	3,216,960	2,666,635	2,312,893
Other revenues
Disaggregation of revenue
Revenues	$ 73,018	$ 67,737	$ 59,285