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Summary of Significant Accounting Policies (Details) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Mar. 31, 2018 USD ($) | Jun. 30, 2017 Payment Quarter
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
Current value assessment period for past due loans secured against real estate |  | 90 days
Threshold period past due for initiation of foreclosure proceedings |  | 120 days
Historical loan loss review period | Quarter |  | 12
Minimum [Member] |  |
Other Real Estate Owned [Abstract] |  |
Typical frequency of periodic reviews |  | 12 months
Maximum [Member] |  |
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] | Scenario, Forecast [Member] |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |
Reduction in retained earnings | $ (150) |
ASU 2017-08 [Member] | Scenario, Forecast [Member] | Minimum [Member] |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |
Quarterly increase in amortization expense | 24 |
ASU 2017-08 [Member] | Scenario, Forecast [Member] | Maximum [Member] |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |
Quarterly increase in amortization expense | $ 30 |

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- Definition Refer to current value assessment period for past due loans secured against real estate, 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 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 Amount of cumulative effect of the change in accounting principle or new accounting pronouncement on retained earnings or other components of equity or net assets in the statement of financial position as of the beginning of the earliest period presented. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Direct Effects of a Change in Accounting Principle -URI http://asc.fasb.org/extlink&oid=66092750 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 250 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=64853466&loc=d3e22580-107794 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Indirect Effects of a Change in Accounting Principle -URI http://asc.fasb.org/extlink&oid=6515603 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Accounting Change -URI http://asc.fasb.org/extlink&oid=6503790 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Retrospective Application -URI http://asc.fasb.org/extlink&oid=6523989 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 250 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b)(3) -URI http://asc.fasb.org/extlink&oid=64853466&loc=d3e22499-107794 Reference 7: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 250 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=64853466&loc=d3e22583-107794 Reference 8: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Change in Accounting Principle -URI http://asc.fasb.org/extlink&oid=6507316 + Details
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