Securities (Narrative) (Details)	3 Months Ended	9 Months Ended	12 Months Ended
Sep. 30, 2021 USD ($) security	Sep. 30, 2020 USD ($)	Sep. 30, 2021 USD ($) security	Sep. 30, 2020 USD ($)	Dec. 31, 2020 USD ($) security
Sales of debt securities available for sale \| $			$ 32,856,000	$ 48,565,000
Securities in unrealized loss position	57		57		11
Equity securities \| $	$ 1,111,000		$ 1,111,000		$ 1,091,000
Realized gain (loss) on equity securities \| $	$ 38,000	$ 2,000	$ 139,000	$ (152,000)
Number of Securities, 12 Months or More	0		0		0
Obligations of U.S. Government Agencies and Corporations [Member]
Securities in unrealized loss position	8		8		3
Number of Securities, 12 Months or More	0		0		0
U.S. Government Sponsored Agencies [Member]
Investment portfolio percentage	11.00%		11.00%
Carrying value of pledged assets \| $	$ 88,705,000		$ 88,705,000		$ 74,614,000
Securities in unrealized loss position	8		8
Obligations of State and Political Subdivisions [Member]
Securities in unrealized loss position	6		6
Number of Securities, 12 Months or More	0		0
Corporate Debt Securities [Member]
Investment portfolio percentage	10.00%		10.00%
Securities in unrealized loss position	5		5		1
Number of Securities, 12 Months or More	0		0		0
Mortgage-Backed Securities [Member]
Investment portfolio percentage	76.00%		76.00%
Securities in unrealized loss position	38		38		7
Other than temporary impairment \| $			$ 0		$ 0
Number of Securities, 12 Months or More	0		0		0
Municipal Bonds [Member]
Investment portfolio percentage	3.00%		3.00%
Debt instrument term			5 years

Investment portfolio percentage.

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- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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Number of investments in debt securities measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for 12 months or longer, without an allowance for credit loss. Includes beneficial interest in securitized financial asset.

+ References

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-Publisher FASB
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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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Number of investments in debt securities measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in unrealized loss position, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI), classified as current.

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Amount of realized gain (loss) from sale of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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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.

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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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