Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Assets
Cash and due from banks	$ 33,889	$ 42,216
Federal funds sold	23,630	32,025
Cash and cash equivalents	57,519	74,241
Mortgage loans held for sale	6,481	3,747
Securities available-for-sale (amortized cost of $465,031 in 2015 and $509,276 in 2014)	471,702	513,056
Federal Home Loan Bank stock and other securities	6,347	6,347
Loans	1,874,010	1,868,550
Less allowance for loan losses	24,882	24,920
Net loans	1,849,128	1,843,630
Premises and equipment, net	40,060	39,088
Bank owned life insurance	30,329	30,107
Accrued interest receivable	6,133	5,980
Other assets	44,564	47,672
Total assets	2,512,263	2,563,868
Deposits
Non-interest bearing	531,190	523,947
Interest bearing	1,579,039	1,599,680
Total deposits	2,110,229	2,123,627
Securities sold under agreements to repurchase	59,877	69,559
Federal funds purchased	14,437	47,390
Accrued interest payable	127	131
Other liabilities	23,248	26,434
Federal Home Loan Bank advances	36,744	36,832
Total liabilities	2,244,662	2,303,973
Stockholders' equity:
Preferred stock, no par value; 1,000,000 shares authorized; no shares issued or outstanding
Common stock, no par value. Authorized 20,000,000 shares; issued and outstanding 14,795,148 and 14,744,684 shares in 2015 and 2014, respectively	10,203	10,035
Additional paid-in capital	39,352	38,191
Retained earnings	214,100	209,584
Accumulated other comprehensive income	3,946	2,085
Total stockholders' equity	267,601	259,895
Total liabilities and stockholders' equity	$ 2,512,263	$ 2,563,868