Other Real Estate Owned and Repossessed Assets - Income and Expense (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Income and expenses related to other real estate owned
Net gain (loss) on sale	$ 224	$ 388	$ 1,003	$ 2,203
Write-downs	(424)	(550)	(1,207)	(1,323)
Net operating expenses	(93)	(509)	(808)	(1,727)
Total	(293)	(671)	(1,012)	(847)
Income and expenses related to repossessed assets
Net gain (loss) on sale	(175)	(112)	(269)	(283)
Write-downs	0	0	0	0
Net operating expenses	(2)	(1)	(5)	(8)
Total	$ (177)	$ (113)	$ (274)	$ (291)