Revenue Recognition (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Dec. 31, 2023
Disaggregation of Revenue [Line Items]
Contract with Customer, Asset, after Allowance for Credit Loss	$ 1,900		$ 1,900		$ 1,900
Operating Revenue	274,754	$ 306,169	545,074	$ 637,085
Accessorial and other revenues	20,000	24,700	40,100	49,300
fuel surcharge [Member]
Disaggregation of Revenue [Line Items]
Fuel surcharge revenue	$ 36,800	$ 41,500	$ 73,000	$ 91,100