Represents adjustable rate of mortgage weighted average term to next adjustment.

No definition available.

Name:	jxsb_AdjustableRateMortgageWeightedAverageTermToNextAdjustment
Namespace Prefix:	jxsb_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Lending Limit

+ References

No definition available.

+ Details

Name:	jxsb_LendingLimit
Namespace Prefix:	jxsb_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Loan Amount That Requires Risk Rating Verification

+ References

No definition available.

+ Details

Name:	jxsb_LoanAmountThatRequiresRiskRatingVerification
Namespace Prefix:	jxsb_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Loan Reimbursement Period

+ References

No definition available.

+ Details

Name:	jxsb_LoanReimbursementPeriod
Namespace Prefix:	jxsb_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Loan Value That Requires Written Appraisals From Licensed Or Certified Appraisers

+ References

No definition available.

+ Details

Name:	jxsb_LoanValueThatRequiresWrittenAppraisalsFromLicensedOrCertifiedAppraisers
Namespace Prefix:	jxsb_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Monthly Mortgage Payment to Monthly Income Percentage

+ References

No definition available.

+ Details

Name:	jxsb_MonthlyMortgagePaymentToMonthlyIncomePercentage
Namespace Prefix:	jxsb_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Monthly Obligations To Monthly Income Percentage

+ References

No definition available.

+ Details

Name:	jxsb_MonthlyObligationsToMonthlyIncomePercentage
Namespace Prefix:	jxsb_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Mortgage Loans On Real Estate Maturity Term

+ References

No definition available.

+ Details

Name:	jxsb_MortgageLoansOnRealEstateMaturityTerm
Namespace Prefix:	jxsb_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Projected Cash Flows To Loans Debt Service Requirement Percentage

+ References

No definition available.

+ Details

Name:	jxsb_ProjectedCashFlowsToLoansDebtServiceRequirementPercentage
Namespace Prefix:	jxsb_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Secured Real Estate to loan Percentage

+ References

No definition available.

+ Details

Name:	jxsb_SecuredRealEstateToLoanPercentage
Namespace Prefix:	jxsb_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

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.

+ References

No definition available.

+ Details

Name:	us-gaap_AccountsNotesAndLoansReceivableLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 33

-URI http://asc.fasb.org/extlink&oid=49124121&loc=SL6953676-111524

+ Details

Name:	us-gaap_FinancingReceivableModificationsNumberOfContracts2
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Post-modification amount of investment in financing receivables modified by troubled debt restructurings.

+ References

+ Details

Name:	us-gaap_FinancingReceivableModificationsPostModificationRecordedInvestment2
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Number of financing receivables that have been modified by troubled debt restructurings within the previous 12 months and for which there was a payment default.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 34

-URI http://asc.fasb.org/extlink&oid=49124121&loc=SL6953682-111524

+ Details

Name:	us-gaap_FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of investment related to financing receivables modified by troubled debt restructurings within the previous 12 months, for which there was a payment default.

+ References

+ Details

Name:	us-gaap_FinancingReceivableModificationsSubsequentDefaultRecordedInvestment1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Details

Name:	us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis=us-gaap_LoansReceivableMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RangeAxis=us-gaap_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_TitleOfIndividualAxis=us-gaap_OfficerMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_TitleOfIndividualAxis=us-gaap_DirectorMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=us-gaap_AutomobileLoanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	jxsb_AutomobileLoanOriginatedCriteriaAxis=jxsb_PurchasePriceMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	jxsb_AutomobileLoanOriginatedCriteriaAxis=jxsb_NadaBookValueMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=jxsb_CommercialRealEstateAndCommercialLoansMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RangeAxis=us-gaap_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_ResidentialPortfolioSegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=jxsb_OneToFourFamilyMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=jxsb_CommercialRealEstateLoanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=jxsb_AgriculturalMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=us-gaap_HomeEquityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=us-gaap_ResidentialRealEstateMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_CommercialPortfolioSegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivablePortfolioSegmentAxis=jxsb_AgriculturalPortfolioSegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_ConsumerPortfolioSegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis=jxsb_FreddieMacAndFederalHomeLoanBankFixedRateMortgageLoanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

LOAN PORTFOLIO COMPOSITION (Detail Textuals)	3 Months Ended		9 Months Ended
LOAN PORTFOLIO COMPOSITION (Detail Textuals)	Sep. 30, 2015 USD ($) Loan	Sep. 30, 2014 USD ($) Loan	Sep. 30, 2015 USD ($) Loan	Sep. 30, 2014 USD ($) Loan
Loans Receivable
Accounts, Notes, Loans and Financing Receivable [Line Items]
Troubled debt restructurings, number of modification \| Loan			4	1
Troubled debt restructurings, recorded investment			$ 168,466	$ 17,428
Loans Receivable \| Maximum
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loan commitments reimbursement period			30 days
Percentage of total applicant's monthly mortgage payment total monthly income			28.00%
Percentage of applicant's total monthly obligations to total monthly income			38.00%
Loans Receivable \| Officer \| Maximum
Accounts, Notes, Loans and Financing Receivable [Line Items]
Lending authority amount			$ 750,000
Loans Receivable \| Director \| Maximum
Accounts, Notes, Loans and Financing Receivable [Line Items]
Lending authority amount			$ 1,000,000
Loans Receivable \| Automobile Loans \| Purchase Price
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loan to value ratios			80.00%
Loans Receivable \| Automobile Loans \| NADA Book Value
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loan to value ratios			100.00%
Loans Receivable \| Commercial Real Estate And Commercial Loans \| Minimum
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loan amount that requires risk rating verification			$ 500,000
Loans Receivable \| Real estate loans \| One-to-Four Family Mortgage Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loan to value ratios			80.00%
Troubled debt restructurings, number of modification \| Loan			1
Troubled debt restructurings, recorded investment			$ 100,492
Loans Receivable \| Real estate loans \| One-to-Four Family Mortgage Loans \| Maximum
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage loans maturity term			30 years
Loans Receivable \| Real estate loans \| Commercial Real Estate Loans \| Minimum
Accounts, Notes, Loans and Financing Receivable [Line Items]
Minimum ratio of property's projected net cash flow to loan's debt service requirement			120.00%
Loan value that requires written appraisals from licensed or certified appraisers	$ 250,000		$ 250,000
Loans Receivable \| Real estate loans \| Commercial Real Estate Loans \| Maximum
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage loans adjustment term			5 years
Loan to value ratios			80.00%
Loans Receivable \| Real estate loans \| Agricultural Real Estate Loans \| Minimum
Accounts, Notes, Loans and Financing Receivable [Line Items]
Minimum ratio of property's projected net cash flow to loan's debt service requirement			120.00%
Loan value that requires written appraisals from licensed or certified appraisers	$ 250,000		$ 250,000
Loans Receivable \| Real estate loans \| Agricultural Real Estate Loans \| Maximum
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loan to value ratios			80.00%
Loans Receivable \| Real estate loans \| Home Equity Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loan to value ratios			95.00%
Troubled debt restructurings, number of modification \| Loan			1
Troubled debt restructurings, recorded investment			$ 1,996
Troubled debt restructurings, subsequent default, number of modifications \| Loan			1	1
TDR's defaulted as they were more than 90 days past due			$ 3,138	$ 3,455
Loans Receivable \| Real estate loans \| Home Equity Loans \| Maximum
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage loans maturity term			10 years
Loans Receivable \| Real estate loans \| Residential Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Troubled debt restructurings, subsequent default, number of modifications \| Loan			3
TDR's defaulted as they were more than 90 days past due			$ 191,763
Loans Receivable \| Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Troubled debt restructurings, number of modification \| Loan
Troubled debt restructurings, recorded investment
Troubled debt restructurings, subsequent default, number of modifications \| Loan			1
TDR's defaulted as they were more than 90 days past due			$ 784,348
Loans Receivable \| Agricultural
Accounts, Notes, Loans and Financing Receivable [Line Items]
Troubled debt restructurings, number of modification \| Loan
Troubled debt restructurings, recorded investment
Loans Receivable \| Consumer loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Troubled debt restructurings, number of modification \| Loan			2	1
Troubled debt restructurings, recorded investment			$ 65,978	$ 17,428
Troubled debt restructurings, subsequent default, number of modifications \| Loan				1
TDR's defaulted as they were more than 90 days past due				$ 694
Freddie Mac and Federal Home Loan Bank Mortgage Loan \| Real estate loans \| One-to-Four Family Mortgage Loans \| Minimum
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage loans adjustment term			15 years