Earnings Per Share (Basic And Diluted Earnings Per Share) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Earnings Per Share [Abstract]
Net Income attributable to Werner	$ 72,290	$ 72,032	$ 126,039	$ 118,524
Weighted average common shares outstanding	64,394	67,926	64,965	67,929
Dilutive effect of stock-based awards	332	290	362	308
Shares used in computing diluted earnings per share	64,726	68,216	65,327	68,237
Basic earnings per share	$ 1.12	$ 1.06	$ 1.94	$ 1.74
Diluted earnings per share	$ 1.12	$ 1.06	$ 1.93	$ 1.74