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Fair Value of Financial Instruments - Assets Measured at Fair Value on Recurring Basis (Details) - USD ($) $ in Thousands | Jun. 30, 2021 | Dec. 31, 2020
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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 | $ 118,735 | $ 84,993
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 | 48,022 | 25,537
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 | 48,022 | 25,537
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 | 48,022 | 25,537
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 | 32,279 | 41,487
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 | 32,279 | 41,487
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 | 32,279 | 41,487
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 | 3,828 | 5,108
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 | 3,828 | 5,108
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 | 3,828 | 5,108
Corporate Notes [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Investment securities available-for-sale, at fair value | 4,355 | 2,784
Corporate Notes [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 | 4,355 | 2,784
Corporate Notes [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 | 4,355 | 2,784
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 | 30,251 | 10,077
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 | 30,251 | 10,077
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 | 30,251 | 10,077
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 | 1,658 | 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 | $ 1,658 | $ 2,610

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