Investments (Summary Of Gross Unrealized Gains And Losses And Fair Values) (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2015	Dec. 31, 2014
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Amortized Cost Basis	$ 130,464	$ 141,003
Available-for-sale Securities, Gross Unrealized Gain	7,835	15,795
Available-for-sale Securities, Gross Unrealized Loss	(57)	(149)
Available-for-sale Securities	138,242	156,649
Corporate Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Amortized Cost Basis	83,036	91,456
Available-for-sale Securities, Gross Unrealized Gain	141	147
Available-for-sale Securities, Gross Unrealized Loss	(56)	(136)
Available-for-sale Securities	83,121	91,467
Debt Securities Issued By The U.S Treasury And Other U.S Government Corporations And Agencies [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Amortized Cost Basis	23,048	26,848
Available-for-sale Securities, Gross Unrealized Gain	34	9
Available-for-sale Securities, Gross Unrealized Loss	(1)	(13)
Available-for-sale Securities	23,081	26,844
Debt Securities Issued By States Of The United States And Political Subdivisions Of The States [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Amortized Cost Basis	3,769	2,088
Available-for-sale Securities, Gross Unrealized Gain	2	5
Available-for-sale Securities, Gross Unrealized Loss	0	0
Available-for-sale Securities	3,771	2,093
Equity Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Amortized Cost Basis	20,611	20,611
Available-for-sale Securities, Gross Unrealized Gain	7,658	15,634
Available-for-sale Securities, Gross Unrealized Loss	0	0
Available-for-sale Securities	$ 28,269	$ 36,245