Other Comprehensive Income (Loss) (Classifications out of accumulated other comprehensive income) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Income Tax Expense	$ (3,821)	$ (1,765)
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	0	0
Amount Reclassified From Accumulated Other Comprehensive Income (Loss)
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	0	0
Unrealized Gains and Losses on Available-for-Sale Securities
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	0	0
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 Gains on Securities	0	0
Income Tax Expense	0	0
Amount Reclassified From Accumulated Other Comprehensive Income (Loss)	$ 0	$ 0