Other Comprehensive Income Tax Effects Allocated to Each Component of Other Comprehensive Income (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Before-Tax Amount
Net unrealized holding gains arising during the period on investment securities available-for-sale, before tax amount	$ (157)	$ 558	$ 2,045	$ 2,775
Reclassification adjustment for net gains on investment securities available-for-sale realized in net income, before tax amount	0		(11)	(8)
Total other comprehensive income, before tax amount	(157)	558	2,034	2,767
Tax (Expense) Benefit
Net unrealized holding gains arising during the period on investment securities available-for-sale, tax	33	(117)	(429)	(583)
Reclassification adjustment for net gains on investment securities available-for-sale realized in net income, tax			2	2
Total other comprehensive income, tax (expense) benefit	(33)	117	427	581
Net unrealized holding gains arising during the period on investment securities available-for-sale	(124)	441	1,616	2,192
Reclassification adjustment for net gains on sales of investment securities available-for-sale realized in net income	0	0	(9)	(6)
Total other comprehensive (loss) income	$ (124)	$ 441	$ 1,607	$ 2,186

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