Pension Benefits (Details Textual)	6 Months Ended
Jun. 30, 2017
Pension Benefits [Line Items]
Minimum number of annual hours	1,000
Vesting term	5 years
Maximum percent of plan assets comprised of AmeriServ Financial, Inc. common stock	10.00%

Defined Benefit Plan, Maximum Percent Of Assets Comprised Of Entity Common Stock.

No definition available.

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