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Fair Value Measurements - Unobservable (Level 3) inputs (Details) - Fair Value, Nonrecurring - Fair Value, Inputs, Level 3 - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended
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Sep. 30, 2025 | Jun. 30, 2025
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Investment, Type [Extensible Enumeration] | Foreclosed and repossessed assets | Foreclosed and repossessed assets
Foreclosed and repossessed assets |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Fair Value Measurements Nonrecurring Unobservable Inputs | $ 1,006 | $ 625
Fair Value Measurements Nonrecurring Weighted Average Discount Applied | 8.0 | 25.6
Foreclosed and repossessed assets | Third party appraisal |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Fair Value Measurements Nonrecurring Valuation Technique | Third party appraisal | Third party appraisal
Foreclosed and repossessed assets | Third party appraisal | Measurement Input, Discount Rate |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Fair Value Measurements Nonrecurring Unobservable Inputs | Marketability discount | Marketability discount
Foreclosed and repossessed assets | Third party appraisal | Measurement Input, Discount Rate | Minimum [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Fair Value Measurements Nonrecurring Range of discounts Applied | 8.00% | 25.60%
Foreclosed and repossessed assets | Third party appraisal | Measurement Input, Discount Rate | Maximum [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Fair Value Measurements Nonrecurring Range of discounts Applied | 8.20% | 25.60%
Collateral dependent loans |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Fair Value Measurements Nonrecurring Unobservable Inputs | $ 20,349 | $ 24,368
Fair Value Measurements Nonrecurring Weighted Average Discount Applied | 22.1 | 23.9
Collateral dependent loans | Collateral value |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Fair Value Measurements Nonrecurring Valuation Technique | Collateral value | Collateral value
Collateral dependent loans | Collateral value | Measurement Input, Discount Rate |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Fair Value Measurements Nonrecurring Unobservable Inputs | Marketability discount | Marketability discount
Collateral dependent loans | Collateral value | Measurement Input, Discount Rate | Minimum [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Fair Value Measurements Nonrecurring Range of discounts Applied | 14.90% | 4.30%
Collateral dependent loans | Collateral value | Measurement Input, Discount Rate | Maximum [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Fair Value Measurements Nonrecurring Range of discounts Applied | 100.00% | 100.00%

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- 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 Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 100 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482078/820-10-55-100 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-3 + Details
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- Definition Description of uncertainty of fair value measurement from use of unobservable input, including, but not limited to, inter-relationships among inputs used in fair value measurement. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (g) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2 + Details
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- Definition Indicates type of investment. Includes, but is not limited to, common stock, preferred stock, convertible security, fixed income security, government security, option purchased, warrant, loan participation and assignment, commercial paper, bankers' acceptance, certificates of deposit, short-term security, repurchase agreement, and other investment company. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 210 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Subparagraph (a)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478795/946-210-50-6 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 210 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (b)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478795/946-210-50-1 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 320 -Name Accounting Standards Codification -Section S99 -Paragraph 2 -Subparagraph (SX 210.12-12A(Column A)(Footnote 2)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477271/946-320-S99-2 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 320 -Name Accounting Standards Codification -Section S99 -Paragraph 6 -Subparagraph (SX 210.12-14(Column A)(Footnote 2)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477271/946-320-S99-6 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 320 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.12-12(Column A)(Footnote 2)(i)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477271/946-320-S99-1 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 320 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.12-12(Column C)(Footnote 5)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477271/946-320-S99-1 Reference 7: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 320 -Name Accounting Standards Codification -Section S99 -Paragraph 3 -Subparagraph (SX 210.12-12B(Column A)(Footnote 1)(a)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477271/946-320-S99-3 Reference 8: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 320 -Name Accounting Standards Codification -Section S99 -Paragraph 3 -Subparagraph (SX 210.12-12B(Column C)(Footnote 2)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477271/946-320-S99-3 Reference 9: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 320 -Name Accounting Standards Codification -Section S99 -Paragraph 6 -Subparagraph (SX 210.12-14(Column F)(Footnote 7)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477271/946-320-S99-6 Reference 10: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 320 -Name Accounting Standards Codification -Section S99 -Paragraph 2 -Subparagraph (SX 210.12-12A(Column C)(Footnote 4)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477271/946-320-S99-2 + Details
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