CONSOLIDATED STATEMENTS OF CHANGES IN SHAREHOLDERS' EQUITY (USD $) In Thousands, except Share data, unless otherwise specified	Total	Common Stock	Retained Earnings	Accumulated Other Comprehensive Income
Beginning Balance at Dec. 31, 2012	$ 233,815	$ 49,667	$ 181,151	$ 2,997
Beginning Balance (in shares) at Dec. 31, 2012		7,622,750
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	5,662		5,662
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	(1,992)			(1,992)
Other comprehensive loss, net of tax
Change in fair value of securities available-for-sale	(2,889)
Comprehensive income	3,670
Stock-based compensation expense	173	173
Exercise of stock options and issuance of restricted stock, net of repurchase for tax withholdings and tax benefit		13,207
Exercise of stock options and issuance of restricted stock, net of repurchase for tax withholdings and tax benefit	(19)	(19)
Cash dividends declared	(2,064)		(2,064)
Ending Balance at Mar. 31, 2013	235,575	49,821	184,749	1,005
Ending Balance (in shares) at Mar. 31, 2013		7,635,957
Beginning Balance at Dec. 31, 2013	231,096	47,783	195,660	(12,347)
Beginning Balance (in shares) at Dec. 31, 2013		7,579,913
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	5,715		5,715
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	769			769
Other comprehensive loss, net of tax
Change in fair value of securities available-for-sale	1,825
Comprehensive income	6,484
Stock-based compensation expense	176	176
Exercise of stock options and issuance of restricted stock, net of repurchase for tax withholdings and tax benefit		18,174
Exercise of stock options and issuance of restricted stock, net of repurchase for tax withholdings and tax benefit	118	118
Common stock repurchased (in shares)		(113,527)
Common stock repurchased	(4,393)	(4,393)
Cash dividends declared	(2,012)		(2,012)
Ending Balance at Mar. 31, 2014	$ 231,469	$ 43,684	$ 199,363	$ (11,578)
Ending Balance (in shares) at Mar. 31, 2014		7,484,560