Significant Accounting Policies - Valuation Allowance (Details) - USD ($) |
Dec. 31, 2025 |
Dec. 31, 2024 |
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| Community Financial System, Inc. 401(k) Employee Stock Ownership Plan | ||
| Significant Accounting Policies | ||
| Valuation allowance | $ 466,000 | $ 438,000 |
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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. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of allowance for credit loss on note receivable from participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)). Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Details
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