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Summary of Significant Accounting Policies and Activities (Details) | Dec. 31, 2020 USD ($) Investments | Mar. 16, 2020 | Mar. 03, 2020 | Dec. 31, 2019 USD ($)
--- | --- | --- | --- | ---
Effect of Fourth Quarter Events [Line Items] |  |  |  |
Real estate loan percentage of total loan | 84.60% |  |  | 82.80%
Federal reserve reduced target federal funds rate basis point |  | 1.00% | 0.50% |
Investment in trusts | $ 403,000 |  |  |
Cash and cash equivalents | 12,600,000 |  |  | $ 6,000,000.0
Line of credit borrowing capacity | 118,500,000 |  |  |
Line of credit | $ 15,000,000.0 |  |  |
Commercial [Member] |  |  |  |
Effect of Fourth Quarter Events [Line Items] |  |  |  |
Total number of loans added under troubled debt restructurings (TDRs) | Investments | 6 |  |  |
Financial difficulty (TDR) [Member] |  |  |  |
Effect of Fourth Quarter Events [Line Items] |  |  |  |
Short-term loan deferrals | $ 3,200,000 |  |  |
Holding Company Line of Credit [Member] |  |  |  |
Effect of Fourth Quarter Events [Line Items] |  |  |  |
Line of credit borrowing capacity | $ 15,000,000.0 |  |  |

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