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Summary of Significant Accounting Policies - Accounting Pronouncement (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2020	Jan. 01, 2020
Retained earnings	$ 213,723	$ 236,579
Deferred tax assets	18,481	$ 18,972
Accounting Standards Update 2016-13 | Revision of Prior Period, Adjustment [Member]
ACL on loans and leases	5,900
Reserve for unfunded commitments	1,700
ACL increase from non-accretable purchase accounting adjustments	$ 2,500
Retained earnings			$ 3,800
Deferred tax assets			$ 1,400

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Amount of increase (decrease) in allowance for credit loss on financing receivable from from the transfer of the non-accretable purchase accounting adjustments on purchase credit impaired loans.

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