Revenue Recognition (Schedule Of Medicare Cap Liability Activity) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Revenue Recognition [Abstract]
Beginning balance January 1,	$ 1,261	$ 2,965
2013 measurement period	(873)
2012 measurement period		(2,577)
Ending balance March 31,	$ 388	$ 388