Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Operating Activities
Net income	$ 12,315	$ 13,241	$ 12,262
Items not requiring cash
Provision for loan losses	1,220	850	125
Depreciation and amortization	4,542	5,006	4,546
Deferred income tax	3,562	1,537	1,926
Increase in cash value of life insurance	(1,113)	(1,159)	(1,184)
Loans originated for sale	(116,887)	(150,620)	(145,749)
Proceeds from sales of loans held for sale	119,711	156,827	149,613
Net gain on sale of loans	(3,887)	(4,761)	(4,176)
Net gain on sale of securities, available for sale	(708)	(1,023)	(436)
Gain on bank owned life insurance		(346)	(204)
Loss on sale of other real estate and repossessed assets	122	210	111
Change in
Interest receivable and other assets	619	(1,349)	(1,321)
Interest payable and other liabilities	287	(5)	277
Other adjustments	259	143	143
Net cash provided by operating activities	20,042	18,551	15,933
Investing Activities
Net change in interest-bearing time deposits	(860)	(993)
Purchases of securities
Purchases of securities, available for sale	(86,499)	(88,161)	(67,414)
Proceeds from maturities and paydowns of securities
Available for sale	26,622	37,872	41,824
Proceeds from sales of securities, available for sale	34,592	57,037	23,109
Redemption of Federal Home Loan Bank stock			(2,154)
Purchase of Federal Home Loan Bank stock	(258)	(443)	(672)
Net change in loans	(32,901)	(92,946)	(67,561)
Proceeds from sales of portfolio loans	18,543
Proceeds from sale of premises and equipment		9,490
Purchases of premises and equipment	(1,809)	(2,079)	(2,413)
Proceeds from real estate owned sales	980	2,497	2,260
Proceeds from sale of real estate held for investment	511
Proceeds from bank owned life insurance		1,120	1,181
Net cash used in investing activities	(41,079)	(76,606)	(67,532)
Net change in
Noninterest-bearing, interest-bearing demand and savings deposits	50,235	39,883	62,642
Certificates of deposit	(1,583)	22,117	(50,580)
Proceeds from FHLB advances	414,700	316,300	355,700
Repayments of FHLB advances	(438,128)	(301,326)	(322,525)
Net repayments other borrowings		(5,312)	(759)
Cash dividends	(4,862)	(4,284)	(3,550)
Stock options exercised	1,156	976	2,011
Stock repurchased		(4,354)
Net cash provided by financing activities	21,518	64,000	42,939
Net Change in Cash and Cash Equivalents	481	5,945	(8,660)
Cash and Cash Equivalents, Beginning of Period	26,860	20,915	29,575
Cash and Cash Equivalents, End of Period	27,341	26,860	20,915
Additional Cash Flows Information
Interest paid	10,505	9,096	8,827
Income tax paid	2,500	2,650	2,850
Transfers from loans to foreclosed assets	624	1,450	1,301
Mortgage servicing rights capitalized	$ 549	482	460
Transfers from fixed assets to other assets		$ 763	$ 702