Revenue Recognition (Schedule Of Disaggregated Revenue) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Subtotal	$ 305,001	$ 319,657	$ 611,792	$ 642,854
Net revenue	297,781	311,935	596,970	627,723
Roto-Rooter [Member]
Subtotal	239,406	225,429	476,405	442,245
Implicit price concessions and credit memos	(5,899)	(5,108)	(11,538)	(10,352)
Net revenue	233,507	220,321	464,867	431,893
Roto-Rooter [Member] | Drain cleaning [Member]
Subtotal	64,532	62,649	131,219	124,406
Roto-Rooter [Member] | Plumbing [Member]
Subtotal	48,885	44,609	96,557	85,922
Roto-Rooter [Member] | Excavation [Member]
Subtotal	55,546	55,114	110,734	107,106
Roto-Rooter [Member] | Other [Member]
Subtotal	155	311	321	598
Roto-Rooter [Member] | Short-Term Core Service Jobs [Member]
Subtotal	169,118	162,683	338,831	318,032
Roto-Rooter [Member] | Water Restoration [Member]
Subtotal	43,673	38,583	84,033	76,018
Roto-Rooter [Member] | Independent Contractors [Member]
Subtotal			42,423	37,785
Implicit price concessions and credit memos	21,005	19,026
Roto-Rooter [Member] | Franchise Fees [Member]
Subtotal			2,688	2,582
Net revenue	1,370	1,255
Roto-Rooter [Member] | All Other [Member]
Subtotal	$ 4,240	$ 3,882	$ 8,430	$ 7,828