Basis Of Presentation (Schedule Of Allowance For Doubtful Accounts) (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2020 USD ($)
BALANCE AT BEGINNING OF PERIOD	$ (353)
(CHARGED) CREDITED TO COSTS AND EXPENSES	(594)
(CHARGED) CREDITED TO OTHER ACCOUNTS	(475)
OTHER	(5)
BALANCE AT END OF PERIOD	(1,427)
Roto-Rooter [Member]
(CHARGED) CREDITED TO COSTS AND EXPENSES	$ (524)