Condensed Consolidated Statements of Comprehensive Income (Unaudited) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Statement Of Income And Comprehensive Income [Abstract]
Net income	$ 3,417	$ 5,311
Change in fair value of derivative instruments:
Change in fair value of derivative instruments for the period	(225)	439
Income tax effect	79	(154)
Changes from derivative instruments	(146)	285
Change in securities available-for-sale:
Unrealized appreciation (depreciation) for the period	4,426	(1,704)
Reclassification adjustment for securities gains realized in income		(368)
Income tax effect	(1,550)	726
Unrealized gains (losses) on available-for-sale securities	2,876	(1,346)
Other Comprehensive Income (Loss), Net of Tax	2,730	(1,061)
Comprehensive Income	$ 6,147	$ 4,250