FAIR VALUE MEASUREMENTS (Details) - EBP 002 - USD ($)	Dec. 31, 2025	Dec. 31, 2024
EBP, Investment, Fair Value and NAV [Line Items]
TOTAL INVESTMENTS	$ 231,205,141	$ 214,021,631
Level 1
EBP, Investment, Fair Value and NAV [Line Items]
TOTAL INVESTMENTS	226,336,720	208,372,306
Tompkins Financial Corporation common stock
EBP, Investment, Fair Value and NAV [Line Items]
TOTAL INVESTMENTS	8,256,435	9,202,840
Tompkins Financial Corporation common stock \| Level 1
EBP, Investment, Fair Value and NAV [Line Items]
TOTAL INVESTMENTS	8,256,435	9,202,840
Collective investment trusts at NAV
EBP, Investment, Fair Value and NAV [Line Items]
TOTAL INVESTMENTS	4,868,421	5,649,325
Collective investment trusts at NAV \| Level 1
EBP, Investment, Fair Value and NAV [Line Items]
TOTAL INVESTMENTS	0	0
Mutual funds
EBP, Investment, Fair Value and NAV [Line Items]
TOTAL INVESTMENTS	218,080,285	199,169,466
Mutual funds \| Level 1
EBP, Investment, Fair Value and NAV [Line Items]
TOTAL INVESTMENTS	$ 218,080,285	$ 199,169,466

Fair value of investment, excluding plan interest in master trust, held by employee stock purchase, saving, or similar plan (employee benefit plan (EBP)). Includes, but is not limited to, derivative, investment measured at net asset value per share as practical expedient, and insurance contract not meeting fully-benefit responsive investment criteria.

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+ Details

- 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.

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