v3.25.2

Allowance for Credit Losses - Loans - Loan modifications to borrowers experiencing financial difficulty (Details) $ in Thousands	3 Months Ended			6 Months Ended
	Jun. 30, 2025 USD ($)	Jun. 30, 2024 USD ($)	Mar. 31, 2024	Jun. 30, 2025 USD ($) loan	Jun. 30, 2024 USD ($)
Financing Receivable, Allowance for Credit Loss [Line Items]
Number of loans modified \| loan				0
Unfunded loan commitments	$ 0	$ 0		$ 0	$ 0
Modified to borrowers which subsequently defaulted	0			0
Extended Maturity
Financing Receivable, Allowance for Credit Loss [Line Items]
Amortized Cost Basis	192			192
Extended Maturity and Interest Rate Reduction
Financing Receivable, Allowance for Credit Loss [Line Items]
Amortized Cost Basis		171			171
Commercial Portfolio Segment \| Commercial and industrial \| Extended Maturity and Interest Rate Reduction
Financing Receivable, Allowance for Credit Loss [Line Items]
Amortized Cost Basis		$ 171			$ 171
Percentage of Total Class of Loans					0.11%
Term extension date		90 days	90 days
Residential mortgages \| Extended Maturity
Financing Receivable, Allowance for Credit Loss [Line Items]
Amortized Cost Basis	$ 192			$ 192
Percentage of Total Class of Loans				0.11%
Term extension date				19 years

Number of loans that have been modified due to borrowers experiencing financial difficulty.

+ References

No definition available.

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- Definition

The amount of financing receivable excluding accrued interest relating unfunded loan.

+ References

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (f)
-Publisher FASB
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
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-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Name Regulation S-K (SK)
-Number 229
-Section 1405
-Paragraph c
-Publisher SEC

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- Definition

Accumulated amortized cost excluding accrued interest, of financing receivable modified for debtor experiencing financial difficulty.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
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- Definition

Amortized cost excluding accrued interest, of financing receivable with payment default in current period and modified within previous 12 months preceding payment default for debtor experiencing financial difficulty.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
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- Definition

Percentage, excluding accrued interest, of financing receivable modified during period for debtor experiencing financial difficulty to total financing receivables.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 42
-Subparagraph (a)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481962/310-10-50-42

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- Definition

Period of increase in weighted average maturity of financing receivable modified for debtor experiencing financial difficulty, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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AMERISERV FINANCIAL INC /PA/ 10-Q