Acquired Loans - Components of the Allowance for Loan Losses on Acquired Loans (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Allowance for Loan and Lease Losses [Roll Forward]
Balance at beginning of period		$ 1,231	$ 4,079	$ 11,397
Transfers	[1]	0	(1,554)	0
Provision for loan losses, acquired loans		42	(1,005)	(7,395)
Net (charge-offs) recoveries		(458)	(289)	77
Balance at end of period		$ 815	$ 1,231	$ 4,079

[1] The allowance for loan losses balance related to the remaining loans acquired in the Bay Bank, Heritage and Reliance acquisitions, which were transferred from acquired impaired loans to LHFI during 2018.