Financial Instruments And Investments (Sale Of Securities And The Related Effects On Pre-Tax Income ) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Investment [Line Items]
Proceeds from sales of available-for-sale securities	$ 12,516	$ 7,547	$ 37,158	$ 36,374	$ 109,095	$ 70,160
Gross realized gains included in pre-tax income	33	249	3,815	3,263	8,410	3,868
Gross realized losses included in pre-tax income	(215)	(147)	(252)	(296)	(464)	(436)
Net gains (losses) in pre-tax income	(182)	102	3,563	2,967	7,946	3,432
Net unrealized holding gains (losses) included in accumulated other comprehensive income	(1,563)	6,070	(549)	7,068	3,210	20,206
Net gains (losses) reclassified out of accumulated other comprehensive income	182	(102)	(3,563)	(2,967)	(7,946)	(3,432)
Net gains (losses) in other comprehensive income	$ (1,381)	$ 5,968	$ (4,112)	$ 4,101	$ (4,736)	$ 16,774