Description of the Plan - Participant accounts and vesting (Details) - Community Financial System, Inc. 401(k) Employee Stock Ownership Plan - USD ($) |
12 Months Ended | |
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Dec. 31, 2025 |
Dec. 31, 2024 |
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| Description of the Plan | ||
| Forfeited accounts allocated to eligible participants | $ 61,655 | $ 87,216 |
| Employer matching contribution, vesting percentage | 100.00% | |
| Employer matching contribution, vesting period | 2 years | |
| Additional employer contribution, vesting percentage | 100.00% | |
| Additional employer contribution, vesting period | 3 years | |
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- Definition Represents the vesting percentage pursuant to additional employer contributions to employee stock purchase, saving, or similar plan (employee benefit plan (EBP)). No definition available.
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- Definition Represents the vesting period pursuant to additional employer contributions to employee stock purchase, saving, or similar plan (employee benefit plan (EBP)). No definition available.
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- Definition Represents the vesting percentage pursuant to employer matching contribution on eligible participant contribution to employee stock purchase, saving, or similar plan (employee benefit plan (EBP)). No definition available.
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- Definition Represents the vesting period pursuant to employer matching contribution on eligible participant contribution to employee stock purchase, saving, or similar plan (employee benefit plan (EBP)). No definition available.
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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 decrease in forfeited nonvested account of employee stock purchase, saving, or similar plan (employee benefit plan (EBP)) from reallocation to participant. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Details
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