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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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.

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The number of quarters over which historical loss rates are generally reviewed.

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No definition available.

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Amount of the effect of a change in accounting principle on amortization expense.

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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.

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No definition available.

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The frequency of periodic reviews for appraisals on foreclosed properties and other real estate owned generally, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The typical frequency of periodic reviews for appraisals on foreclosed properties and other real estate owned, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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.

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No definition available.

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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.

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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.

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No definition available.

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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

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-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

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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

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Threshold period past due for financing receivable to write off as uncollectible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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