XML 12 R43.htm IDEA: XBRL DOCUMENT
v3.20.1

Disclosures About Fair Value of Assets and Liabilities (Details Textual) $ in Thousands | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | ---
Mar. 31, 2020 USD ($) | Mar. 31, 2019 USD ($) | Mar. 31, 2020 USD ($) Loans | Mar. 31, 2019 USD ($) | Jun. 30, 2019 USD ($) Loans
Disclosures About Fair Value of Assets and Liabilities (Textual) |  |  |  |  |
Other real estate owned written down amount |  |  | $ 577 |  | $ 117
Impairment charge |  |  | $ 9 | $ 23 |
Number of impairment loans | Loans |  |  | 7 |  | 7
Other Real Estate Owned [Member] |  |  |  |  |
Disclosures About Fair Value of Assets and Liabilities (Textual) |  |  |  |  |
Other real estate owned written down amount | $ 12 | $ 0 | $ 36 | $ 54 |

X
- References No definition available. + Details
Name: | kffb_DisclosuresAboutFairValueOfAssetsAndLiabilitiesTextualAbstract
Namespace Prefix: | kffb_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Represents the number of impairment loans. + References No definition available. + Details
Name: | kffb_NumberOfImpairmentLoans
Namespace Prefix: | kffb_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- References No definition available. + Details
Name: | kffb_OtherRealEstateOwnedWrittenDownAmount
Namespace Prefix: | kffb_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition For the asset that is reclassified back to held and used from held-for-sale, the amount of impairment charge that is recognized on the reclassification date. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 35 -Paragraph 44 -URI http://asc.fasb.org/extlink&oid=29634951&loc=d3e1756-110224 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 45 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=109226348&loc=d3e2459-110228 + Details
Name: | us-gaap_ImpairmentChargeOnReclassifiedAssets
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Details
Name: | us-gaap_InvestmentTypeAxis=kffb_OtherRealEstateOwnedMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |