Accumulated Other Comprehensive Income (Summary Of Accumulated Other Comprehensive Income, Net Of Taxes) (Details) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive income, net	$ 425,064	$ 447,082
Net Unrealized Gains (Losses) On Available For Sale Securities [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive income, net	571,472	577,588
Net Unrealized Foreign Exchange Gains (Losses) [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive income, net	(45,187)	(26,771)
Accumulated Defined Benefit Adjustment [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive income, net	$ (101,221)	$ (103,735)