CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Cash flows from operating activities:
Net income	$ 12,772	$ 10,359	$ 9,166
Adjustments to reconcile net income to net cash provided by operating activities:
Provision for loan losses	5,000	3,900	3,500
Depreciation and amortization	1,762	1,843	1,612
Net amortization on securities	5,573	2,400	1,454
Amortization of core deposit intangible	67	42
Share based compensation expense	1,343	1,047	881
Net securities gains	(2,647)	(135)	(1,303)
Increase in accrued interest receivable	(496)	(787)	(474)
(Increase) decrease in other assets	(2,287)	1,593	2,041
Increase (decrease) in accrued expenses and other liabilities	1,737	(1,582)	(1,454)
Net cash provided by operating activities	22,824	18,680	15,423
Cash flows from investing activities:
Purchases of securities available for sale	(511,979)	(302,760)	(226,213)
Purchases of securities, restricted	(31,355)	(315)	(2,055)
Purchases of securities held to maturity	(132,304)	(83,911)	(137,240)
Proceeds from sales of securities available for sale	151,959	14,084	31,446
Redemption of securities, restricted	30,037	225	1,976
Maturities, calls and principal payments of securities available for sale	266,095	196,886	175,013
Maturities, calls and principal payments of securities held to maturity	89,123	61,844	66,056
Net increase in loans	(186,226)	(73,029)	(57,070)
Proceeds from loan sale	575
Purchase of premises and equipment	(3,592)	(2,031)	(3,989)
Net cash acquired in business combination		2,309
Net cash used in investing activities	(327,667)	(186,698)	(152,076)
Cash flows from financing activities:
Net increase in deposits	221,137	214,252	123,455
Net increase (decrease) increase in federal funds purchased and FHLB overnight borrowings	44,500	(7,000)	5,000
Net increase (decrease) of FHLB term advances	15,000	(5,016)
Net (decrease) increase in repurchase agreements	(4,507)	527	1,370
Net proceeds from issuance of common stock	10,507	28,088	1,395
Net proceeds from exercise of stock options			17
Repurchase of surrendered stock from exercise of stock options and vesting of restricted stock awards	(175)	(128)	(37)
Excess tax (expense) benefit from share based compensation	(18)	(16)	11
Cash dividends paid	(9,898)	(6,061)	(5,787)
Net cash provided by financing activities	276,546	224,646	125,424
Net (decrease) increase in cash and cash equivalents	(28,297)	56,628	(11,229)
Cash and cash equivalents at beginning of period	79,546	22,918	34,147
Cash and cash equivalents at end of period	51,249	79,546	22,918
Cash paid for:
Interest	7,727	7,730	7,838
Income tax	5,260	4,550	5,922
Noncash investing and financing activities:
Dividends declared and unpaid at end of period			1,467
Transfers from portfolio loans to loans held for sale		2,300
Financing of sale of loans held for sale	1,725
Transfers from portfolio loans to OREO	250
Acquisition of noncash assets and liabilities:
Fair value of assets acquired		66,566
Fair value of liabilities assumed		$ 65,059