Consolidated Statement of Changes in Shareholders' Equity - USD ($) shares in Thousands, $ in Thousands	Common Stock	Capital Surplus	Retained Earnings	Accumulated Other Comprehensive Income (Loss)	Total
BALANCE-beginning of period at Dec. 31, 2013	$ 208	$ 179,219	$ 19,918	$ (127)	$ 199,218
BALANCE-beginning of period (in shares) at Dec. 31, 2013	20,771
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income			8,162		8,162
Net change in unrealized gains and losses on available-for-sale securities, net of taxes and reclassification adjustment				1,199	1,199
Issuance of common stock in connection with the exercise of stock options		76			76
Issuance of common stock in connection with the exercise of stock options (in shares)	9
Stock-based compensation expense		97			97
BALANCE-end of period at Jun. 30, 2014	$ 208	179,392	28,080	1,072	208,752
BALANCE-end of period (in shares) at Jun. 30, 2014	20,780
BALANCE-beginning of period at Dec. 31, 2014	$ 262	252,421	34,660	1,062	288,405
BALANCE-beginning of period (in shares) at Dec. 31, 2014	26,176
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income			8,787		8,787
Net change in unrealized gains and losses on available-for-sale securities, net of taxes and reclassification adjustment				111	111
Issuance of common stock in connection with the exercise of stock options	$ 1	887			888
Issuance of common stock in connection with the exercise of stock options (in shares)	94
Stock-based compensation expense		461			461
BALANCE-end of period at Jun. 30, 2015	$ 263	$ 253,769	$ 43,447	$ 1,173	$ 298,652
BALANCE-end of period (in shares) at Jun. 30, 2015	26,270