Consolidated Statements of Comprehensive Income (Unaudited) (Parenthetical) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Statement Of Income And Comprehensive Income [Abstract]
Unrealized gains (losses) on arising during the period	$ (1)	$ 54	$ 136	$ 205
Reclassification adjustment for amortization of unrealized losses on securities transferred	1	2	4	5
Reclassification adjustment for securities gains included in net income	$ 0	$ (1)	$ 0	$ (1)

Amount of tax expense (benefit) of reclassification adjustment from accumulated other comprehensive income for unrealized gain (loss) realized upon the sale of available-for-sale securities.

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Amount of tax expense (benefit) for reclassification adjustment from accumulated other comprehensive income (loss) for unrealized gain (loss) of investment classified as available-for-sale transferred to equity method.

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-Publisher FASB
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Amount, before adjustment, of tax expense (benefit) for unrealized holding gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). Excludes tax expense (benefit) for unrealized gain (loss) on investment in debt security measured at amortized cost (held-to-maturity) from transfer to available-for-sale.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
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