Segment Information (Summary Of Segment Information) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Segment Reporting Information [Line Items]
Revenues	$ 827,606	$ 702,891	$ 2,428,487	$ 1,969,151
Operating Income	76,261	71,324	234,695	210,658
Depreciation and amortization	70,397	68,615	206,097	196,431
Truckload Transportation Services
Segment Reporting Information [Line Items]
Revenues	621,866	527,697	1,793,899	1,481,846
Operating Income	74,117	62,856	214,214	193,592
Depreciation and amortization	64,579	63,247	189,283	180,305
Werner Logistics
Segment Reporting Information [Line Items]
Revenues	187,138	157,968	580,007	437,494
Operating Income	5,145	7,650	26,316	16,151
Depreciation and amortization	2,423	2,205	7,042	6,511
Other
Segment Reporting Information [Line Items]
Revenues	18,469	17,004	54,928	49,128
Operating Income	(1,091)	1,406	(185)	3,935
Depreciation and amortization	2,875	2,675	8,347	8,165
Corporate
Segment Reporting Information [Line Items]
Revenues	535	434	1,402	1,222
Operating Income	(1,910)	(588)	(5,650)	(3,020)
Depreciation and amortization	520	488	1,425	1,450
Subtotal
Segment Reporting Information [Line Items]
Revenues	$ 828,008	$ 703,103	$ 2,430,236	$ 1,969,690