Other Real Estate Owned and Repossessed Assets - Income and Expense (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Income and expenses related to other real estate owned
Net gain (loss) on sale	$ 23	$ 768	$ 779	$ 1,815
Write-downs	(132)	(504)	(783)	(773)
Net operating expenses	(318)	(710)	(715)	(1,218)
Total	(427)	(446)	(719)	(176)
Income and expenses related to repossessed assets
Net gain (loss) on sale	(60)	(93)	(94)	(171)
Write-downs	0	0	0	0
Net operating expenses	(2)	(3)	(3)	(6)
Total	$ (62)	$ (96)	$ (97)	$ (177)