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v3.25.2

Fair Value of Assets and Liabilities - Non Recurring Basis (Details) - Level 3 - Non Recurring | Jun. 30, 2025 USD ($) | Jun. 30, 2024 USD ($)
--- | --- | ---
Foreclosed assets (OREO), net |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Alternative investment | $ 996,373 | $ 1,375,140
Alternative Investment, Valuation Technique [Extensible Enumeration] | mara:CollateralValuationMember | mara:CollateralValuationMember
Alternative Investment, Measurement Input [Extensible Enumeration] | us-gaap:MeasurementInputDiscountRateMember | us-gaap:MeasurementInputDiscountRateMember
Collateral dependent financial assets |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Alternative investment | $ 66,645 |
Alternative Investment, Valuation Technique [Extensible Enumeration] | mara:AppraisalValuationMember | mara:AppraisalValuationMember
Alternative investment, measurement input | 0 | 0
Alternative Investment, Measurement Input [Extensible Enumeration] | us-gaap:MeasurementInputDiscountRateMember | us-gaap:MeasurementInputDiscountRateMember
Minimum |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Alternative investment, measurement input | 0.10 | 0.10
Maximum |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Alternative investment, measurement input | 0.75 | 0.75

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- Definition Fair value of investment other than investment in equity security, investment in debt security and equity method investment. Includes, but is not limited to, investment in certain entities that calculate net asset value per share. Example includes, but is not limited to, investment in hedge fund, venture capital fund, private equity fund, and real estate partnership or fund. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -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 2: http://www.xbrl.org/2003/role/exampleRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 107 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482078/820-10-55-107 Reference 3: http://www.xbrl.org/2003/role/exampleRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 103 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482078/820-10-55-103 Reference 4: 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 5: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (bbb)(2)(i) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2 Reference 6: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (bbb)(2) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2 Reference 7: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (bbb)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2 Reference 8: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 35 -Paragraph 54B -Publisher FASB -URI https://asc.fasb.org/1943274/2147482134/820-10-35-54B Reference 9: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 6A -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-6A + Details
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