v3.25.4

Basis Of Presentation (Details) | Dec. 31, 2025
--- | ---
Third Federal Savings, MHC | Common Stock |
Mutual Holding Company, Percentage Of Ownership In Registrant | 80.90%

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- Definition Mutual Holding Companies Percentage Of ownership In Registrant + References No definition available. + Details
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Namespace Prefix: | tfsl_
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Balance Type: | na
Period Type: | instant

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- Details
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Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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- Details
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Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |