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Regulatory Matters - Regulatory Matters (Details) $ in Thousands | Jun. 30, 2025 USD ($) | Jun. 30, 2024 USD ($)
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The Bank of Greene County [Member] |  |
Compliance with Regulatory Capital [Abstract] |  |
Total risk-based capital, actual amount (in Dollars) | $ 293,952 | $ 273,460
Total risk-based capital, actual ratio | 0.166 | 0.171
Total risk-based capital for capital adequacy purposes, amount (in Dollars) | $ 141,305 | $ 127,873
Total risk-based capital for capital adequacy purposes, ratio | 0.08 | 0.08
Total risk-based capital to be well capitalized under prompt corrective action provisions, amount (in Dollars) | $ 176,632 | $ 159,841
Total risk-based capital to be well capitalized under prompt corrective action provisions, ratio | 0.10 | 0.10
Total risk-based capital for capital conservation buffer, actual | 0.0864 | 0.0911
Total risk-based capital for capital conservation buffer, required | 0.025 | 0.025
Tier 1 risk-based capital, actual amount (in Dollars) | $ 271,869 | $ 253,468
Tier 1 risk-based capital, actual ratio | 0.154 | 0.159
Tier 1 risk-based capital for capital adequacy purposes, amount (in Dollars) | $ 105,979 | $ 95,905
Tier 1 risk-based capital for capital adequacy purposes, ratio | 0.06 | 0.06
Tier 1 risk-based capital to be well capitalized under prompt corrective action provisions, amount (in Dollars) | $ 141,305 | $ 127,873
Tier 1 risk-based capital to be well capitalized under prompt corrective action provisions, ratio | 0.08 | 0.08
Tier 1 risk-based capital for capital conservation buffer, actual | 0.0939 | 0.0986
Tier 1 risk-based capital for capital conservation buffer, required | 2.50% | 2.50%
Common equity tier 1 capital, actual amount (in Dollars) | $ 271,869 | $ 253,468
Common equity tier 1 capital, actual ratio | 0.154 | 0.159
Common equity tier 1 capital for capital adequacy purposes, amount (in Dollars) | $ 79,484 | $ 71,929
Common equity tier 1 capital for capital adequacy purposes, ratio | 0.045 | 0.045
Common equity tier 1 capital to be well capitalized under prompt corrective action provisions, amount (in Dollars) | $ 114,811 | $ 103,897
Common equity tier 1 capital to be well capitalized under prompt corrective action provisions, ratio | 0.065 | 0.065
Common equity tier 1 capital for capital conservation buffer, actual | 0.1089 | 0.1136
Common equity tier 1 capital for capital conservation buffer, required | 2.50% | 2.50%
Tier 1 leverage ratio, actual amount (in Dollars) | $ 271,869 | $ 253,468
Tier 1 leverage ratio, actual ratio | 0.092 | 0.093
Tier 1 leverage ratio for capital adequacy purposes, amount (in Dollars) | $ 117,646 | $ 109,102
Tier 1 leverage ratio for capital adequacy purposes, ratio | 0.04 | 0.04
Tier 1 leverage ratio to be well capitalized under prompt corrective action provisions, amount (in Dollars) | $ 147,057 | $ 136,378
Tier 1 leverage ratio to be well capitalized under prompt corrective action provisions, ratio | 0.05 | 0.05
Tier 1 leverage ratio for capital conservation buffer, actual | 5.24% | 5.29%
Tier 1 leverage ratio for capital conservation buffer, required | 2.50% | 2.50%
Greene County Commercial Bank [Member] |  |
Compliance with Regulatory Capital [Abstract] |  |
Total risk-based capital, actual amount (in Dollars) | $ 122,243 | $ 110,319
Total risk-based capital, actual ratio | 0.469 | 0.495
Total risk-based capital for capital adequacy purposes, amount (in Dollars) | $ 20,871 | $ 17,830
Total risk-based capital for capital adequacy purposes, ratio | 0.08 | 0.08
Total risk-based capital to be well capitalized under prompt corrective action provisions, amount (in Dollars) | $ 26,089 | $ 22,288
Total risk-based capital to be well capitalized under prompt corrective action provisions, ratio | 0.10 | 0.10
Total risk-based capital for capital conservation buffer, actual | 0.3886 | 0.415
Total risk-based capital for capital conservation buffer, required | 0.025 | 0.025
Tier 1 risk-based capital, actual amount (in Dollars) | $ 122,243 | $ 110,319
Tier 1 risk-based capital, actual ratio | 0.469 | 0.495
Tier 1 risk-based capital for capital adequacy purposes, amount (in Dollars) | $ 15,654 | $ 13,373
Tier 1 risk-based capital for capital adequacy purposes, ratio | 0.06 | 0.06
Tier 1 risk-based capital to be well capitalized under prompt corrective action provisions, amount (in Dollars) | $ 20,871 | $ 17,830
Tier 1 risk-based capital to be well capitalized under prompt corrective action provisions, ratio | 0.08 | 0.08
Tier 1 risk-based capital for capital conservation buffer, actual | 0.4086 | 0.435
Tier 1 risk-based capital for capital conservation buffer, required | 2.50% | 2.50%
Common equity tier 1 capital, actual amount (in Dollars) | $ 122,243 | $ 110,319
Common equity tier 1 capital, actual ratio | 0.469 | 0.495
Common equity tier 1 capital for capital adequacy purposes, amount (in Dollars) | $ 11,740 | $ 10,029
Common equity tier 1 capital for capital adequacy purposes, ratio | 0.045 | 0.045
Common equity tier 1 capital to be well capitalized under prompt corrective action provisions, amount (in Dollars) | $ 16,958 | $ 14,487
Common equity tier 1 capital to be well capitalized under prompt corrective action provisions, ratio | 0.065 | 0.065
Common equity tier 1 capital for capital conservation buffer, actual | 0.4236 | 0.45
Common equity tier 1 capital for capital conservation buffer, required | 2.50% | 2.50%
Tier 1 leverage ratio, actual amount (in Dollars) | $ 122,243 | $ 110,319
Tier 1 leverage ratio, actual ratio | 0.091 | 0.091
Tier 1 leverage ratio for capital adequacy purposes, amount (in Dollars) | $ 53,543 | $ 48,385
Tier 1 leverage ratio for capital adequacy purposes, ratio | 0.04 | 0.04
Tier 1 leverage ratio to be well capitalized under prompt corrective action provisions, amount (in Dollars) | $ 66,929 | $ 60,481
Tier 1 leverage ratio to be well capitalized under prompt corrective action provisions, ratio | 0.05 | 0.05
Tier 1 leverage ratio for capital conservation buffer, actual | 5.13% | 5.12%
Tier 1 leverage ratio for capital conservation buffer, required | 2.50% | 2.50%

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- Definition The minimum common equity tier 1 capital ratio required for capital conservation buffer (minimum common equity tier 1 capital required for capital conservation buffer divided by risk-weighted assets) under the regulatory framework for prompt corrective action. + References No definition available. + Details
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- Definition Tier 1 Leverage Capital for capital conservation buffer divided by average assets as defined in the regulations. + References No definition available. + Details
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- Definition The minimum Tier 1 Leverage Capital ratio for capital conservation buffer (Tier 1 Leverage Capital required for capital conservation buffer divided by average assets) as defined in the regulations. + References No definition available. + Details
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- Definition Minimum capital conservation buffer percentage required to avoid restriction on payout amount of eligible retained income as defined by regulatory framework. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 942 -SubTopic 505 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (c)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477270/942-505-50-1 + Details
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- Definition Ratio of Tier 1 risk-based capital to risk-weighted assets as defined by regulatory framework. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 942 -SubTopic 505 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (c)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477270/942-505-50-1 + Details
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