Consolidated Statements of Comprehensive Earnings (Parentheticals) - USD ($)	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Net unrealized gains (losses) on available-for-sale securities arising during period, taxes	$ 2,522,000	$ 2,901,000	$ 1,398,000
Reclassification adjustment for net losses on the sale of securities included in net earnings, taxes	$ 231,000	$ 70,000	$ 170,000

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.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=121641772&loc=d3e640-108580

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 9
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=121645371&loc=d3e27357-111563

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