Business Combinations and Asset Acquisitions (Narrative) (Details) $ in Thousands			12 Months Ended
	Nov. 22, 2021 USD ($) count	Jul. 01, 2021 USD ($) count	Dec. 31, 2021 USD ($)
Business Acquisition [Line Items]
Estimated fair value of intangible assets			$ 57,200
Acquisition of ECM Transport Group [Member]
Business Acquisition [Line Items]
Percentage of equity interests acquired		80.00%
Total purchase price (fair value of consideration)		$ 141,291
Percentage of equity interests owned by noncontrolling interest		20.00%
Trucks | count		500
Trailers | count		2,000
Operational facilities | count		8
Drop lots | count		18
Fixed rate term loan amount used to acquire ECM		$ 100,000
Business acquisition transaction costs		$ 1,000
Payments to acquire businesses deposited in escrow			1,500
Acquisition of NEHDS [Member]
Business Acquisition [Line Items]
Percentage of equity interests acquired	100.00%
Total purchase price (fair value of consideration)	$ 63,054
Trucks | count	400
Warehouse facilities | count	19
Business acquisition transaction costs	$ 600
Payments to acquire businesses deposited in escrow			3,100
Minimum potential undiscounted amount of future earnout payments			0
Maximum potential undiscounted amount of future earnout payments			4,000
Fair value of contingent consideration arrangement			$ 2,500