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Summary of Significant Accounting Policies (Details) $ in Millions | 9 Months Ended |
--- | --- | ---
Sep. 30, 2018 USD ($) Payment Quarter | Dec. 31, 2017 USD ($)
New Accounting Standards [Abstract] |  |
Equity securities |  | $ 25.0
Unrealized holding loss on securities |  | $ (0.6)
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 Standards [Abstract] |  |
Net present value of all potential lease payments | $ 10.1 |
Other Real Estate Owned [Abstract] |  |
Typical frequency of periodic reviews | 12 months |
Maximum [Member] |  |
New Accounting Standards [Abstract] |  |
Net present value of all potential lease payments | $ 20.3 |
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 |

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- Definition The maximum number of delinquent payments that a closed-end loan (excluding conventional 1-4 family residential loans and installment and revolving loans secured by real estate) may be delinquent before being charged-off. If a loan is considered uncollectable, it is charged off earlier. + References No definition available. + Details
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- Definition Refers to the past due period after which loans must be well secured and in the process of collection to continue accruing interest, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
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- Definition Period for which principal and interest payments must remain current for reclassifying nonaccrual loans as accruing loans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
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- Definition Threshold period past due for the initiation of foreclosure proceedings, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
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- Definition This item represents the cost of equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments for other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any. + References No definition available. + Details
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