Investments (Gross Gains And Losses Realized On Sales Of Investments) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Investments [Abstract]
Equity securities, Realized Gain	$ 43,420	$ 20,835	$ 29,446
Equity securities, Realized Loss	(45,607)	(23,048)	(29,945)
Equity securities, Realized Gain (Loss)	(2,187)	(2,213)	(499)
Fixed maturity securities, Realized Gain	549	604	3,327
Fixed maturity securities, Realized Loss	(3,563)	(2,701)	(19,133)
Fixed maturity securities, Realized Gain (Loss)	(3,014)	(2,097)	(15,806)
Short-term investments, Realized Gain	61	21	6
Short-term investments, Gross Realized Losses	(2,429)	(20)	(530)
Short-term investments, Realized Gain (Loss)	$ (2,368)	$ 1	$ (524)