SCHEDULE H, LINE 4i - SCHEDULE OF ASSETS (HELD AT END OF YEAR) (Details) - NBT Bancorp Inc. 401(k) and Employee Stock Ownership Plan [Member] |
12 Months Ended |
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Dec. 31, 2025 | |
| SCHEDULE H, LINE 4i - SCHEDULE OF ASSETS (HELD AT END OF YEAR) [Abstract] | |
| Plan name | 401(k) AND EMPLOYEE STOCK OWNERSHIP PLAN |
| EIN# | 16-1268674 |
| Plan # | 002 |
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- Definition The Tax Identification Number (TIN), also known as an Employer Identification Number (EIN), is a unique 9-digit value assigned by the IRS. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Name of employee stock purchase, saving, or similar plan (employee benefit plan (EBP)). Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Plan number of employee stock purchase, saving, or similar plan (employee benefit plan (EBP)), in three-digit numeric format. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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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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- Details
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