v3.19.1

Borrowed Funds - Additional Information (Details) - USD ($) |  | 12 Months Ended |  |  |  |  |
--- | --- | --- | --- | --- | --- | --- | ---
Nov. 24, 2015 | Dec. 31, 2018 | Dec. 31, 2017 | Oct. 01, 2017 | Jul. 30, 2016 | Jun. 15, 2016 | Jul. 30, 2014
Debt Instrument [Line Items] |  |  |  |  |  |  |
Interest rate |  |  |  |  |  |  |
Federal funds purchased |  | $ 2,000,000 | $ 0 |  |  |  |
Federal home loan bank advances |  | $ 2,000,000 | $ 2,000,000 |  |  |  |
Senior Notes | Senior promissory note due July 31, 2019 |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Face amount |  |  |  |  |  |  | $ 5,000,000
Repurchased amount |  |  |  |  | $ 3,000,000 |  |
Interest rate |  | 0.00% | 5.50% | 5.50% | 5.00% |  |
Junior Subordinated Debt | Junior subordinated debentures due June 15, 2036 |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Interest rate |  | 4.68% | 3.56% |  |  |  |
Junior Subordinated Debt | Junior subordinated debentures due June 15, 2036 | London Interbank Offered Rate (LIBOR) |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Basis spread on variable rate |  | 1.87% |  |  |  |  |
Senior Subordinated Notes | Other subordinated notes due December 1, 2025 |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Face amount | $ 13,500,000 |  |  |  |  |  |
Interest rate | 6.95% | 6.95% | 6.95% |  |  |  |
Basis spread on variable rate | 5.33% |  |  |  |  |  |
Debt issuance costs | $ 278,231 |  |  |  |  |  |
Line of Credit |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Maximum borrowing capacity |  | $ 28,000,000 |  |  |  |  |
Capital Securities | Junior Subordinated Debt | Junior subordinated debentures due June 15, 2036 |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Face amount |  |  |  |  |  | $ 2,000,000 |
Securities issued (in shares) |  |  |  |  |  | 2,000 |
Common Securities | Junior Subordinated Debt | Junior subordinated debentures due June 15, 2036 |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Face amount |  |  |  |  |  | $ 62,000 |
Federal Home Loan Bank | Line of Credit |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
FHLB maximum borrowing capacity, percent of assets |  | 25.00% |  |  |  |  |
FHLB available borrowing capacity |  | $ 185,600,000 | $ 84,100,000 |  |  |  |
Pacific Coast Bankers Bank | Line of Credit |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Interest rate |  | 3.28% | 0.00% |  |  |  |
Federal funds purchased |  | $ 2,000,000 | $ 0 |  |  |  |
Financial Network | Certificates of Deposit |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Maximum borrowing capacity |  | $ 161,200,000 | 152,400,000 |  |  |  |
Maximum borrowing capacity, percent of assets |  | 15.00% |  |  |  |  |
Pledged Loans | Federal Home Loan Bank | Line of Credit |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Current borrowing capacity |  | $ 235,200,000 | 78,800,000 |  |  |  |
Pledged Loans | Federal Reserve Bank Of Richmond | Line of Credit |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Current borrowing capacity |  | 13,100,000 | 17,900,000 |  |  |  |
Federal home loan bank advances |  | 0 | 0 |  |  |  |
Collateral Pledged | Federal Home Loan Bank | Line of Credit |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Investments at fair value |  | $ 6,700,000 | $ 7,500,000 |  |  |  |

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