Other Comprehensive Income (Loss) (Classifications out of accumulated other comprehensive income) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Income Tax Expense	$ (4,249)	$ (2,937)	$ (6,014)	$ (6,239)
Amount Reclassified From Accumulated Other Comprehensive Income (Loss)
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Amount Reclassified From Accumulated Other Comprehensive Income (Loss)	629	170	629	471
Unrealized Gains and Losses on Available-for-Sale Securities | Amount Reclassified From Accumulated Other Comprehensive Income (Loss)
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net Gain (Loss) on Securities	968	262	968	725
Income Tax Expense	(339)	(92)	(339)	(254)
Amount Reclassified From Accumulated Other Comprehensive Income (Loss)	$ 629	$ 170	$ 629	$ 471