Other Comprehensive Income (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Components of accumulated other comprehensive income
Unrealized Gains (Losses) on Securities Available-for-Sale, Beginning balance			$ 12,671	$ 11,036
Unrealized Gains (Losses) on Derivative Instruments, Beginning balance			(3,570)	(3,194)
Beginning balance, Total			9,101	7,842
Unrealized Gains (Losses) on Securities Available-for-Sale, Other comprehensive income (loss) before reclassifications			(9,016)	1,352
Unrealized Gains (Losses) on Derivative Instruments, Other comprehensive income (loss) before reclassifications	1,028	(785)	1,313	(419)
Other comprehensive income (loss) before reclassifications, Total			(7,703)	933
Unrealized Gains (Losses) on Securities Available-for-Sale, Amounts reclassified from other comprehensive income			(368)
Unrealized Gains (Losses) on Derivative Instruments,, Amounts reclassified from other comprehensive income
Amounts reclassified from other comprehensive income, Total			(239)
Unrealized Gains (Losses) on Securities Available-for-Sale, Period change	(7,909)	787	(9,255)	1,352
Unrealized Gains (Losses) on Derivative Instruments, Period change			1,313	(419)
Period change, Total			(7,942)	933
Unrealized Gains (Losses) on Securities Available-for-Sale, Ending balance	3,416	12,388	3,416	12,388
Unrealized Gains (Losses) on Derivative Instruments, Ending balance	(2,257)	(3,613)	(2,257)	(3,613)
Ending balance, Total	$ 1,159	$ 8,775	$ 1,159	$ 8,775