RISK AND UNCERTAINTIES (Details) - 401(k) Profit Sharing Plan - USD ($)	Dec. 31, 2025	Dec. 31, 2024
RISK AND UNCERTAINTIES
Threshold percentage of concentration to total assets available for plan benefits	10.00%	10.00%
Common/collective funds \| Pathroad Tactical Capital Appreciation and Income Fund
RISK AND UNCERTAINTIES
Investments held	$ 8,142,095	$ 7,083,405
Common/collective funds \| Pathroad Tactical Balanced Growth and Income Fund
RISK AND UNCERTAINTIES
Investments held	$ 7,290,414	$ 6,386,278

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

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 275
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 18
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482861/275-10-50-18

+ Details

Name:	us-gaap-ebp_EbpRiskAndUncertaintyConcentrationOfInvestmentAtFairValueToNetAssetsAmount
Namespace Prefix:	us-gaap-ebp_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Threshold percentage for investment applied to benchmark used for identifying concentration risk of employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

+ References

+ Details

Name:	us-gaap-ebp_EbpRiskAndUncertaintyConcentrationOfInvestmentBenchmarkThresholdPercentage
Namespace Prefix:	us-gaap-ebp_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- 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

+ Details

Name:	us-gaap-ebp_EbpRiskAndUncertaintyLineItems
Namespace Prefix:	us-gaap-ebp_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	dei_LegalEntityAxis=asrv_EBP002Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_InvestmentTypeAxis=us-gaap_DefinedBenefitPlanCommonCollectiveTrustMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_InvestmentIssuerNameAxis=asrv_PathroadTacticalCapitalAppreciationIncomeMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_InvestmentIssuerNameAxis=asrv_PathroadTacticalBalancedGrowthIncomeMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: