Investments (Gross Gains And Losses Realized On Sales Of Investments) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Fixed Maturity Securities [Member]
Investments [Line Items]
Gross Realized Gains	$ 604	$ 3,327	$ 631
Gross Realized Losses	(2,701)	(19,133)	(495)
Net	(2,097)	(15,806)	136
Equity Securities [Member]
Investments [Line Items]
Gross Realized Gains	20,835	29,446	41,305
Gross Realized Losses	(23,048)	(29,945)	(58,764)
Net	(2,213)	(499)	(17,459)
Short-term Investments [Member]
Investments [Line Items]
Gross Realized Gains	21	6	0
Gross Realized Losses	(20)	(530)	(1,396)
Net	$ 1	$ (524)	$ (1,396)