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Investments (Amortized Cost and Fair Values Classified by Contractual Maturity Date) (Details) - USD ($) $ in Thousands | Sep. 30, 2021 | Dec. 31, 2020
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Schedule of Investments [Line Items] |  |
Amortized Cost: Due after one year through five years | $ 4,404 |
Amortized Cost: Due after five years through ten years | 10,057 |
Amortized Cost: Due after ten years | 69,054 |
Available For Sale Debt Maturities Amortized Cost Sub Total | 83,515 |
Fair Value: Due after one year through five years | 4,466 |
Fair Value: Due after five years through ten years | 10,198 |
Fair Value: Due after ten years | 65,958 |
Available For Sale Debt Maturities Fair Value Sub Total | 80,622 |
Available-for-sale Securities, Amortized Cost Basis | 241,197 | $ 230,464
Available-for-sale Securities | 235,564 | 226,885
Amortized Cost: Due after ten years, Held to maturity | 20,169 |
Fair Value: Due after ten years, Held to maturity | 29,074 |
Held-to-maturity Securities | 61,979 | 68,263
Held-to-maturity securities, fair value | 71,707 | 77,612
Residential mortgage-backed agencies [Member] |  |
Schedule of Investments [Line Items] |  |
Available-for-sale Securities, Amortized Cost Basis | 30,936 | 22,999
Available-for-sale Securities | 30,354 | 22,899
Held-to-maturity Securities | 32,113 | 34,597
Held-to-maturity securities, fair value | 32,601 | 35,732
Commercial mortgage-backed agencies [Member] |  |
Schedule of Investments [Line Items] |  |
Available-for-sale Securities, Amortized Cost Basis | 55,980 | 32,549
Available-for-sale Securities | 55,509 | 33,042
Held-to-maturity Securities | 9,697 | 11,716
Held-to-maturity securities, fair value | 10,032 | 12,303
Collateralized mortgage obligations [Member] |  |
Schedule of Investments [Line Items] |  |
Available-for-sale Securities, Amortized Cost Basis | 70,766 | 70,372
Available-for-sale Securities | $ 69,079 | 70,637
Held-to-maturity Securities |  | 1,348
Held-to-maturity securities, fair value |  | $ 1,406

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