Name:	asrv_EmployeeBenefitPlanEmployeeContributionIncrementalPercentage
Namespace Prefix:	asrv_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

Percentage of participant compensation eligible for employer non-elective contribution for participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

No definition available.

Name:	asrv_EmployeeBenefitPlanEmployerContributionParticipantCompensationNonElectiveContributionPercentage
Namespace Prefix:	asrv_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

Represents the information relating to number of common/collective portfolios in which employee contributions are invested.

No definition available.

Name:	asrv_EmployeeBenefitPlanNumberOfCommonCollectivePortfolios
Namespace Prefix:	asrv_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

Represents the information relating to number of money market/cash equivalent funds in which employee contributions are invested.

No definition available.

Name:	asrv_EmployeeBenefitPlanNumberOfMoneyMarketAndCashEquivalentFunds
Namespace Prefix:	asrv_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

Represents the information relating to number of mutual funds in which employee contributions are invested.

No definition available.

Name:	asrv_EmployeeBenefitPlanNumberOfMutualFunds
Namespace Prefix:	asrv_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

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.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 962
-SubTopic 205
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478416/962-205-50-1

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

Percentage of employer matching contribution on eligible participant contribution to employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 962
-SubTopic 325
-Name Accounting Standards Codification
-Section 55
-Paragraph 17
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478873/962-325-55-17

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

Percentage of participant compensation eligible for employer matching contribution for participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

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

Percentage of maximum pretax annual compensation that participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)), is permitted to contribute to total pretax annual compensation.

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

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

Name:	srt_RangeAxis=srt_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	srt_RangeAxis=srt_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	srt_StatementScenarioAxis=asrv_NonUnionEmployeesHiredAfterDecember312012Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: