XML 63 R51.htm IDEA: XBRL DOCUMENT
v3.22.4

Fair Value Measurements and Fair Value of Financial Instruments, Fair Value Inputs, Assets, Quantitative Information (Details) $ in Thousands | Dec. 31, 2022 USD ($) | Jun. 30, 2022 USD ($)
--- | --- | ---
Nonrecurring [Member] |  |  |
Additional Quantitative Information about Assets Measured at Fair Value [Abstract] |  |  |
Impaired loans |  | $ 6,151 | $ 7,054
Foreclosed real estate |  |  | 68
Level 3 [Member] | Appraisal of Collateral [Member] |  |  |
Additional Quantitative Information about Assets Measured at Fair Value [Abstract] |  |  |
Impaired loans | [1] | 4,578 | 4,333
Foreclosed real estate | [1] |  | 68
Level 3 [Member] | Discounted Cash Flow [Member] |  |  |
Additional Quantitative Information about Assets Measured at Fair Value [Abstract] |  |  |
Impaired loans |  | 1,573 | 2,721
Level 3 [Member] | Nonrecurring [Member] |  |  |
Additional Quantitative Information about Assets Measured at Fair Value [Abstract] |  |  |
Impaired loans |  | $ 6,151 | 7,054
Foreclosed real estate |  |  | $ 68
Level 3 [Member] | Appraisal Adjustments [Member] | Appraisal of Collateral [Member] |  |  |
Additional Quantitative Information about Assets Measured at Fair Value [Abstract] |  |  |
Foreclosed real estate, measurement input | [1],[2] |  | 0.1046
Level 3 [Member] | Appraisal Adjustments [Member] | Appraisal of Collateral [Member] | Minimum [Member] |  |  |
Additional Quantitative Information about Assets Measured at Fair Value [Abstract] |  |  |
Impaired loans, measurement input | [1],[2] | 0.0706 | 0.0706
Level 3 [Member] | Appraisal Adjustments [Member] | Appraisal of Collateral [Member] | Maximum [Member] |  |  |
Additional Quantitative Information about Assets Measured at Fair Value [Abstract] |  |  |
Impaired loans, measurement input | [1],[2] | 0.3373 | 0.3373
Level 3 [Member] | Appraisal Adjustments [Member] | Appraisal of Collateral [Member] | Weighted Average [Member] |  |  |
Additional Quantitative Information about Assets Measured at Fair Value [Abstract] |  |  |
Impaired loans, measurement input | [1],[2] | 0.197 | 0.2167
Foreclosed real estate, measurement input | [1],[2] |  | 0.1046
Level 3 [Member] | Liquidation Expenses [Member] | Appraisal of Collateral [Member] | Minimum [Member] |  |  |
Additional Quantitative Information about Assets Measured at Fair Value [Abstract] |  |  |
Impaired loans, measurement input | [1],[3] | 0.0398 | 0.0398
Level 3 [Member] | Liquidation Expenses [Member] | Appraisal of Collateral [Member] | Maximum [Member] |  |  |
Additional Quantitative Information about Assets Measured at Fair Value [Abstract] |  |  |
Impaired loans, measurement input | [1],[3] | 0.0558 | 0.0558
Level 3 [Member] | Liquidation Expenses [Member] | Appraisal of Collateral [Member] | Weighted Average [Member] |  |  |
Additional Quantitative Information about Assets Measured at Fair Value [Abstract] |  |  |
Impaired loans, measurement input | [1],[3] | 0.0433 | 0.0472
Level 3 [Member] | Discount Rate [Member] | Discounted Cash Flow [Member] | Minimum [Member] |  |  |
Additional Quantitative Information about Assets Measured at Fair Value [Abstract] |  |  |
Impaired loans, measurement input |  | 0.0379 | 0.0419
Level 3 [Member] | Discount Rate [Member] | Discounted Cash Flow [Member] | Maximum [Member] |  |  |
Additional Quantitative Information about Assets Measured at Fair Value [Abstract] |  |  |
Impaired loans, measurement input |  | 0.1195 | 0.1195
Level 3 [Member] | Discount Rate [Member] | Discounted Cash Flow [Member] | Weighted Average [Member] |  |  |
Additional Quantitative Information about Assets Measured at Fair Value [Abstract] |  |  |
Impaired loans, measurement input |  | 0.0663 | 0.0621
[1] | Fair value is generally determined through independent third-party appraisals of the underlying collateral, which generally includes various Level 3 inputs which are not observable.
[2] | Appraisals may be adjusted downwards by management for qualitative factors such as economic conditions. Higher downward adjustments are caused by negative changes to the collateral or conditions in the real estate market, actual offers or sales contracts received or age of the appraisal.
[3] | Appraisals are adjusted downwards by management for qualitative factors such as the estimated costs to liquidate the collateral.

X
- Definition This element represents the fair value disclosure of foreclosed real estate. + References No definition available. + Details
Name: | gcbc_ForeclosedRealEstateFairValueDisclosure
Namespace Prefix: | gcbc_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Value of input used to measure foreclosed real estate. + References No definition available. + Details
Name: | gcbc_ForeclosedRealEstateMeasurementInput
Namespace Prefix: | gcbc_
Data Type: | xbrli:decimalItemType
Balance Type: | na
Period Type: | instant

X
- Definition This element represents the fair value disclosure of impaired loan receivable as presented on the statement of financial position which may include mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts, or any other loans which are due the Company as of the balance sheet date. + References No definition available. + Details
Name: | gcbc_ImpairedLoansFairValueDisclosure
Namespace Prefix: | gcbc_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Value of input used to measure impaired loans. + References No definition available. + Details
Name: | gcbc_ImpairedLoansMeasurementInput
Namespace Prefix: | gcbc_
Data Type: | xbrli:decimalItemType
Balance Type: | na
Period Type: | instant

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

X
- Details
Name: | us-gaap_FairValueByMeasurementFrequencyAxis=us-gaap_FairValueMeasurementsNonrecurringMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByFairValueHierarchyLevelAxis=us-gaap_FairValueInputsLevel3Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ValuationTechniqueAxis=us-gaap_MarketApproachValuationTechniqueMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ValuationTechniqueAxis=us-gaap_ValuationTechniqueDiscountedCashFlowMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_MeasurementInputTypeAxis=us-gaap_MeasurementInputComparabilityAdjustmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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: |

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

X
- Details
Name: | us-gaap_MeasurementInputTypeAxis=us-gaap_MeasurementInputDiscountForLackOfMarketabilityMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_MeasurementInputTypeAxis=us-gaap_MeasurementInputDiscountRateMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |