Non-performing Assets Including Troubled Debt Restructurings (Narrative) (Details) - USD ($)	9 Months Ended
Sep. 30, 2015	Sep. 30, 2014
Nonperforming Assets Including Troubled Debt Restructurings [Abstract]
Aggregate of multiple consecutive maturity date extensions delay in payment, days	120 days
Timely payments on contract terms for minimum consecutive months prior to consideration for removing loan from TDR status	6 months
Minimum consecutive months payment for removing the loan from non-accrual status	6 months
ALL reserve for TDR's	$ 524,000	$ 503,000

Aggregate of multiple consecutive maturity date extensions delay in payment.

No definition available.

Name:	asrv_AggregateOfMultipleConsecutiveMaturityDateExtensionsDelayInPaymentDays
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Data Type:	xbrli:durationItemType
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Period Type:	duration

Allowance for loan and lease losses pertaining to troubled debt restructurings.

No definition available.

Name:	asrv_AllowanceForLoanAndLeaseLossesTroubledDebtRestructurings
Namespace Prefix:	asrv_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Minimum number of consecutive months payment for removing the loan from non-accrual status.

No definition available.

Name:	asrv_MinimumNumberOfConsecutiveMonthsPaymentForRemovingLoanFromNonaccrualStatus
Namespace Prefix:	asrv_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

Non performing assets including trouble debt restructurings.

No definition available.

Name:	asrv_NonperformingAssetsIncludingTroubledDebtRestructuringsAbstract
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Timely payments on contract terms for minimum consecutive months prior to consideration for removing loan from TDR status.

No definition available.

Name:	asrv_TimelyPaymentsOnContractTermsForMinimumConsecutiveMonthsPriorToConsiderationForRemovingLoanFromTdrStatus
Namespace Prefix:	asrv_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration