Investment Securities (Narrative) (Details) - USD ($)	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Investment Securities [Abstract]
Fair value of investments reported at less than historical cost	$ 64,400,000	$ 206,914,000
Percentage of Bank portfolio	16.70%	55.80%
Securities pledged as collateral	$ 2,700,000	$ 0
Proceeds from sales of securities, available for sale	30,833,000	67,002,000	$ 34,592,000
Gross realized gain on sale of securities	1,000,000	892,000	776,000
Gross realized losses on sale of securities	5,000	88,000	$ 68,000
Other than temporary impairment losses investments available for sale securities	$ 0	$ 0
Percentage of recovery estimate depository institutions	10.00%
Percentage of recovery estimate insurance companies	15.00%

Percentage of recovery estimate depository institutions.

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Percentage of recovery estimate insurance companies.

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- Definition

Percentage Of Total Investment Portfolio In Unrealized Loss Position Fair Value

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- Definition

This item represents the gross loss realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

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No definition available.

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Amount of realized gain on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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-Section 50
-Paragraph 9
-Subparagraph (a)
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Amount of restricted investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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-Publisher FASB
-Name Accounting Standards Codification
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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in unrealized loss position.

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Amount of other-than-temporary impairment (OTTI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), recognized in earnings and other comprehensive loss (OCI).

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Amount of cash inflow from sale of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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