Other Comprehensive Income (Loss) (Narrative) (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015
Class of Stock [Line Items]
Accumulated other comprehensive income (loss)	$ (47,865)		$ (55,659)
Net unrealized gains (losses) on cash flow hedges
Class of Stock [Line Items]
Accumulated other comprehensive income (loss)	(12,137)	$ (12,177)	(12,217)	$ (12,297)	$ (12,336)	$ (12,504)
Net unrealized gains (losses) on cash flow hedges | Valuation Allowance of Deferred Tax Assets
Class of Stock [Line Items]
Accumulated other comprehensive income (loss)	(12,100)
Net unrealized gains (losses) on investment securities available for sale
Class of Stock [Line Items]
Accumulated other comprehensive income (loss)	(36,586)	$ (43,444)	$ (44,324)	$ 22,459	$ 10,747	$ (18,222)
Net unrealized gains (losses) on investment securities available for sale | Valuation Allowance of Deferred Tax Assets
Class of Stock [Line Items]
Accumulated other comprehensive income (loss)	$ (13,300)