Income Taxes - Components of Net Deferred Tax Assets (Liabilities) (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Deferred tax assets:
Allowance for loan losses	$ 4,480	$ 4,410
Nonaccrual loan interest	610	576
Other real estate owned valuation allowance	199	360
Deferred compensation	1,335	1,353
Net unrealized losses on securities	81	0
Acquisition accounting adjustments	3,215	4,641
Accrued pension liability	100	0
Other	796	840
Total deferred tax assets	10,816	12,180
Deferred tax liabilities:
Depreciation	1,030	951
Accretion of discounts on securities	113	320
Core deposit intangibles	602	939
Net unrealized gains on securities	0	2,219
Prepaid pension expense	0	9
Trust preferred fair value adjustment	581	616
Other	243	239
Total deferred tax liabilities	2,569	5,293
Net deferred tax assets	$ 8,247	$ 6,887