Income Taxes - Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Deferred tax asset
Allowance for loan losses and OREO losses		$ 9,004	$ 14,035
Fair value adjustments related to acquisition		2,123	3,953
Reserve for indemnification losses		641	875
Deferred compensation		1,383	2,005
Share-based compensation		769	1,036
Interest on nonaccrual loans		475	1,088
Cash flow hedges			22
Other		2,363	3,722
Deferred tax asset		16,758	26,736
Deferred tax liability
Goodwill and other intangible assets		(2,810)	(3,848)
Core deposit intangible		(76)	(307)
Defined benefit plan		(934)	(116)
Depreciation		(632)	(180)
Cash flow hedges		(43)
Net unrealized gain on securities available for sale		(170)	(746)
Deferred tax liability		(4,665)	(5,197)
Net deferred tax asset		$ 12,093	$ 21,539
Federal corporate income tax rate		35.00%	35.00%	35.00%
Forecast
Deferred tax liability
Federal corporate income tax rate	21.00%