Loans - Changes in Accretable Yield on PCI Loans (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Accretable Yield Movement Schedule [Roll Forward]
Beginning balance	$ 3,699	$ 3,807	$ 2,610
Additions	0	763	2,052
Deletions	(43)	(11)	(15)
Accretion	(1,291)	(1,647)	(1,734)
Reclassifications from non-accretable difference	559	787	894
Ending Balance	$ 2,924	$ 3,699	$ 3,807