Acquisitions (Unaudited Pro Forma Condensed Consolidated Income Statement Information) (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Business Acquisition [Line Items]
Net service revenues	$ 1,084,759	$ 991,566	$ 936,601
Operating income from continuing operations	96,679	73,353	69,081
Net income from continuing operations	$ 65,436	$ 46,270	$ 47,622
Basic income per share	$ 4.09	$ 2.92	$ 3.03
Diluted income per share	$ 4.01	$ 2.86	$ 2.96