XML 57 R42.htm IDEA: XBRL DOCUMENT
v3.22.2.2

Securities (Details) - USD ($) | 12 Months Ended
--- | ---
Jun. 30, 2022 | Jun. 30, 2021
Securities (Details) [Line Items] |  |
Held-to-maturity mortgage-backed securities | $ 242,000 | $ 258,000
Gross unrealized losses | 18,000 | 2,000
Pledged securities | 1,700,000 | 1,800,000
Time deposits | 1,500,000 | $ 1,500,000
Minimum [Member] |  |
Securities (Details) [Line Items] |  |
Unrealized loss position | 3,000 |
Maximum [Member] |  |
Securities (Details) [Line Items] |  |
Unrealized loss position | $ 15,000 |

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

X
- Definition Pledged securities. + References No definition available. + Details
Name: | kffb_PledgedSecurities
Namespace Prefix: | kffb_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

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

X
- Definition Unrealized loss position. + References No definition available. + Details
Name: | kffb_UnrealizedLoss
Namespace Prefix: | kffb_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Fair value of securitized, pay-through debt securities collateralized by real estate mortgage loans classified as held-to-maturity. + References No definition available. + Details
Name: | us-gaap_MortgageBackedSecuritiesHeldToMaturityFairValueDisclosure
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition The carrying amount (fair value) as of the balance sheet date of securities held that had been pledged by counterparties under financing and lending arrangements, pursuant to which the entity has the right by agreement or custom to sell or re-pledge such securities. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 5 -URI https://asc.fasb.org/extlink&oid=123577603&loc=d3e5086-111524 + Details
Name: | us-gaap_SecuritiesHeldAsCollateralAtFairValue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | srt_RangeAxis=srt_MinimumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_MaximumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |