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Loans (Additional Information) (Details) | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2019 USD ($) loan | Jun. 30, 2018 USD ($) loan | Jun. 30, 2019 USD ($) loan | Jun. 30, 2018 USD ($) loan | Dec. 31, 2018 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Number of loans modified as troubled debt restructurings | loan | 0 | 0 | 0 | 0 |
Additional lending amount to customers whose loan terms has been modified in troubled debt restructuring | $ 0 |  | $ 0 |  | $ 0
Number of loans modified as troubled debt restructuring subsequently defaulted | loan | 0 | 0 | 0 | 0 |
Threshold amount to individually classify loans by credit risk | $ 250,000 |  | $ 250,000 |  |
Carrying amount of consumer mortgage loans secured by residential real estate properties | 10,000 |  | 10,000 |  | $ 58,000
Loans Acquired With Deteriorated Credit Quality |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Increase in allowance for loan losses | 147,000 | $ 0 | 424,000 | $ 30,000 |
Reversal of allowance for loan losses | $ 0 | $ 3,000 | $ 0 | $ 3,000 |

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