Revenue Recognition (Schedule Of Disaggregated Revenue) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Gross revenue	$ 1,348,112	$ 1,231,010	$ 1,289,433
Net revenue	1,315,065	1,201,564	1,261,246
Roto-Rooter [Member]
Gross revenue	975,936	955,859	897,769
Implicit price concessions and credit memos	(26,584)	(22,460)	(19,754)
Net revenue	949,352	933,399	878,015
Roto-Rooter [Member] | Drain cleaning [Member]
Gross revenue	249,069	261,606	254,773
Roto-Rooter [Member] | Plumbing [Member]
Gross revenue	196,695	194,274	176,051
Roto-Rooter [Member] | Excavation [Member]
Gross revenue	233,196	222,945	215,190
Roto-Rooter [Member] | Other [Member]
Gross revenue	936	708	1,138
Roto-Rooter [Member] | Short-Term Core [Member]
Gross revenue	679,896	679,533	647,152
Roto-Rooter [Member] | Water Restoration [Member]
Gross revenue	185,550	169,434	153,115
Roto-Rooter [Member] | Independent Contractors [Member]
Gross revenue	85,749	84,442	76,858
Roto-Rooter [Member] | Franchise Fees [Member]
Gross revenue	5,658	5,591	5,068
Roto-Rooter [Member] | Other [Member]
Implicit price concessions and credit memos	$ 19,083	$ 16,859	$ 15,576