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Summary of Significant Accounting Policies (Details) $ in Thousands | 3 Months Ended |
--- | --- | ---
Mar. 31, 2018 USD ($) Payment Quarter | Dec. 31, 2017 USD ($)
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |
Equity securities |  | $ 25,000
Unrealized holding loss on securities |  | $ (600)
Federal corporate income tax rate | 21.00% |
Loans [Abstract] |  |
Past due period after which loans must be well secured and in the process of collection to continue accruing interest | 90 days |
Period of current principal and interest payments for reclassifying nonaccrual loans as accruing loans | 6 months |
Allowance for Loan and Lease Losses [Abstract] |  |
Number of delinquent monthly payments before loan charge off | Payment | 5 |
Threshold period past due for initiation of foreclosure proceedings | 120 days |
Current value assessment period for past due loans secured against real estate | 90 days |
Historical loan loss review period | Quarter | 12 |
Minimum [Member] |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |
Net present value of all potential lease payments | $ 10,100 |
Other Real Estate Owned [Abstract] |  |
Typical frequency of periodic reviews | 12 months |
Maximum [Member] |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |
Net present value of all potential lease payments | $ 20,300 |
Other Real Estate Owned [Abstract] |  |
Typical frequency of periodic reviews | 18 months |
Frequency of periodic reviews in general | 24 months |
Commercial [Member] | Unsecured Commercial Loan [Member] |  |
Allowance for Loan and Lease Losses [Abstract] |  |
Charge off threshold for loans considered uncollectible | 90 days |
Consumer [Member] | Closed-End Consumer Loan [Member] |  |
Allowance for Loan and Lease Losses [Abstract] |  |
Charge off threshold for loans considered uncollectible | 120 days |
ASU 2017-08 [Member] |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |
Quarterly increase in amortization expense | $ 27 |

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