Other Comprehensive Income (Loss) (Narrative) (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Jun. 30, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Dec. 31, 2011
Class of Stock [Line Items]
Accumulated other comprehensive income	$ (29,514)	$ (33,060)	$ 4,101	$ 16,156	$ 7,003	$ 21,093
Net Unrealized Gains (Losses) on Cash Flow Hedges [Member]
Class of Stock [Line Items]
Accumulated other comprehensive income	(13,168)	(13,237)	(13,373)	(14,016)
Net Unrealized Gains (Losses) on Cash Flow Hedges [Member] | Valuation Allowance of Deferred Tax Assets [Member]
Class of Stock [Line Items]
Accumulated other comprehensive income	(12,100)
Net Unrealized Gains (Losses) on Investment Securities Available for Sale [Member]
Class of Stock [Line Items]
Accumulated other comprehensive income	(17,168)	(20,689)	17,111	29,556
Net Unrealized Gains (Losses) on Investment Securities Available for Sale [Member] | Valuation Allowance of Deferred Tax Assets [Member]
Class of Stock [Line Items]
Accumulated other comprehensive income	$ 13,300