Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Assets
Cash and due from banks	$ 42,610	$ 32,901
Federal funds sold and interest bearing due from banks	25,093	22,019
Mortgage loans held for sale	14,047	4,381
Securities available for sale (amortized cost of $377,383 in 2012 and $343,059 in 2011)	386,440	352,185
Federal Home Loan Bank stock	5,180	4,948
Other securities	1,000	1,001
Loans	1,584,594	1,544,845
Less allowance for loan losses	31,881	29,745
Net loans	1,552,713	1,515,100
Premises and equipment, net	36,532	36,611
Bank owned life insurance	28,149	27,143
Accrued interest receivable	5,091	5,964
Other assets	51,407	50,844
Total assets	2,148,262	2,053,097
Deposits
Non-interest bearing	396,159	313,587
Interest bearing	1,385,534	1,304,152
Total deposits	1,781,693	1,617,739
Securities sold under agreements to repurchase	59,045	66,026
Federal funds purchased	16,552	37,273
Accrued interest payable	166	232
Other liabilities	22,949	42,810
Federal Home Loan Bank advances	31,882	60,431
Subordinated debentures	30,900	40,900
Total liabilities	1,943,187	1,865,411
Stockholders' equity
Preferred stock, no par value; 1,000,000 shares authorized; no shares issued or outstanding
Common stock, no par value; 20,000,000 shares authorized; issued and outstanding 13,915,265 shares in 2012 and 13,819,319 shares in 2011	7,273	6,953
Additional paid-in capital	17,731	14,599
Retained earnings	174,650	160,672
Accumulated other comprehensive income	5,421	5,462
Total stockholders' equity	205,075	187,686
Total liabilities and stockholders' equity	$ 2,148,262	$ 2,053,097