XML 45 R34.htm IDEA: XBRL DOCUMENT v3.8.0.1

Loans Receivable (Details Textual) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Sep. 30, 2017	Jun. 30, 2017
Financing Receivable, Modifications [Line Items]
TDRs carrying value	$ 136
Net of a purchase credit discount	388	$ 388
Troubled Debt Restructuring [Member] | Residential Real Estate One to Four Family [Member]
Financing Receivable, Modifications [Line Items]
TDRs, Post-Modification Outstanding Recorded Investment	$ 1,706	$ 1,533
Percentage Of Bankruptcy Proceedings To Borrower	15.90%

X

- Definition

Repersent loan carrying value of TDR.

+ References

No definition available.

+ Details

Name:	kffb_LoanCarryingValue
Namespace Prefix:	kffb_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- Definition

Represents the percentage of bankruptcy proceedings to borrower.

+ References

No definition available.

+ Details

Name:	kffb_PercentageOfBankruptcyProceedingsToBorrower
Namespace Prefix:	kffb_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

X

- Definition

For loans and debt securities, 1) for which at acquisition it was probable that the investor would be unable to collect all contractually required payments receivable, and 2) for which it is further probable that the investor will not be able to collect all cash flows expected at acquisition (plus any additional cash flows expected due to changes in estimate after acquisition), the allowance for credit losses recorded to reflect the impairment since acquisition.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5275-111524

+ Details

Name:	us-gaap_CertainLoansAndDebtSecuritiesAcquiredInTransferAllowanceForCreditLossesDueToSubsequentImpairment
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

X

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

X

- Definition

Post-modification amount of investment in financing receivables 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=84173941&loc=SL6953676-111524

+ Details

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

X

- Details

Name:	kffb_TroubledDebtRestructuringAxis=kffb_TroubledDebtRestructuringMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	kffb_ResidentialRealEstateFamilyAxis=kffb_ResidentialRealEstateOneToFourFamilyMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: