Purchased Loans - Changes in Restructured Loans (Details) - Purchased $ in Thousands	12 Months Ended
	Dec. 31, 2020 USD ($) loan	Dec. 31, 2019 USD ($) loan
Number of Loans
Beginning balance (loans) | loan	54	54
Additional advances or loans with concessions (loans) | loan	13	5
Reclassified from nonperforming (loans) | loan	1	14
Reclassified as nonperforming (loans) | loan	(14)	(11)
Paid in full (loans) | loan	(5)	(7)
Charge-offs (loans) | loan	(1)	(1)
Principal paydowns (loans) | loan	0	0
Measurement period adjustment on recently acquired loans (loans) | loan		0
Ending balance (loans) | loan	48	54
Recorded Investment
Beginning balance | $	$ 7,275	$ 7,495
Additional advances or loans with concessions | $	5,378	3,168
Reclassified as performing | $	74	1,931
Reclassified as nonperforming | $	(2,563)	(1,964)
Paid in full | $	(978)	(370)
Charge-offs | $	(3)	(101)
Principal paydowns | $	(496)	(508)
Measurement period adjustment on recently acquired loans | $		(2,376)
Ending balance | $	$ 8,687	$ 7,275