PARTY-IN-INTEREST TRANSACTIONS (Details) - 401(k) Profit Sharing Plan - USD ($)	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024
RISK AND UNCERTAINTIES
Investment at fair value to net assets amount	$ 47,695,781	$ 41,948,204
Sponsor
RISK AND UNCERTAINTIES
Dividends income	18,640	16,071
Common/collective funds
RISK AND UNCERTAINTIES
Investment at fair value to net assets amount	24,100,209	22,089,426
Common/collective funds \| Trustee
RISK AND UNCERTAINTIES
Investment at fair value to net assets amount	$ 24,100,209	$ 21,570,989
Investment at fair value to net assets percentage	50.00%	51.00%
AmeriServ Financial, Inc. common stock
RISK AND UNCERTAINTIES
Investment at fair value to net assets amount	$ 534,424	$ 390,420
AmeriServ Financial, Inc. common stock \| Sponsor
RISK AND UNCERTAINTIES
Investment in shares	167,531	145,679

Percentage of investment at fair value held by employee stock purchase, saving, or similar plan (employee benefit plan (EBP)), to net assets available for benefit representing concentration risk at or above applicable threshold.

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