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Fair Value of Financial Instruments - Assets Measured at Fair Value on Recurring Basis (Details) - USD ($) $ in Thousands | Dec. 31, 2020 | Dec. 31, 2019
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Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Investment securities available-for-sale, at fair value | $ 84,993 | $ 94,016
Fair Value, Recurring [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Investment securities available-for-sale, at fair value | 2,784 |
Fair Value, Recurring [Member] | Other Assets [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Investment securities available-for-sale, at fair value |  | 301
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Investment securities available-for-sale, at fair value | 2,784 |
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Other Assets [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Investment securities available-for-sale, at fair value |  | 301
Residential Mortgage Backed Securities [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Investment securities available-for-sale, at fair value | 25,537 | 46,345
Residential Mortgage Backed Securities [Member] | Fair Value, Recurring [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Investment securities available-for-sale, at fair value | 25,537 | 46,345
Residential Mortgage Backed Securities [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Investment securities available-for-sale, at fair value | 25,537 | 46,345
Commercial Mortgage Backed Securities [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Investment securities available-for-sale, at fair value | 41,487 | 43,373
Commercial Mortgage Backed Securities [Member] | Fair Value, Recurring [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Investment securities available-for-sale, at fair value | 41,487 | 43,373
Commercial Mortgage Backed Securities [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Investment securities available-for-sale, at fair value | 41,487 | 43,373
US States and Political Subdivisions Debt Securities [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Investment securities available-for-sale, at fair value | 5,108 | 4,218
US States and Political Subdivisions Debt Securities [Member] | Fair Value, Recurring [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Investment securities available-for-sale, at fair value | 5,108 | 4,218
US States and Political Subdivisions Debt Securities [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Investment securities available-for-sale, at fair value | 5,108 | 4,218
US Treasury Securities [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Investment securities available-for-sale, at fair value | 10,077 | 80
US Treasury Securities [Member] | Fair Value, Recurring [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Investment securities available-for-sale, at fair value | 10,077 | 80
US Treasury Securities [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Investment securities available-for-sale, at fair value | 10,077 | $ 80
Other Liabilities [Member] | Fair Value, Recurring [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Investment securities available-for-sale, at fair value | 2,610 |
Other Liabilities [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Investment securities available-for-sale, at fair value | $ 2,610 |

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