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The aggregate of all deposit liabilities held by the entity, including foreign and domestic, interest and noninterest bearing; may include demand deposits, saving deposits, Negotiable Order of Withdrawal (NOW) and time deposits among others that do not have stated maturities.

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Deposits with no stated maturities fair value disclosure.

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Deposits with stated maturities fair value disclosure.

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Regulatory assets fair value disclosure.

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Fair value portion of trade and related party payables and accrued expenses.

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Fair value portion of amount due from customers or clients for goods or services, including trade receivables, that have been delivered or sold in the normal course of business, and amounts due from others, including related parties.

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Interest, dividends, rents, ancillary and other revenues earned but not yet received by the entity on its investments.

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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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The carrying amount of a life insurance policy on an officer, executive or employee for which the reporting entity (a bank) is entitled to proceeds from the policy upon death of the insured or surrender of the insurance policy.

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Fair value portion of the amount that could be realized under a life insurance contract or contracts owned by the entity, commonly known as corporate-owned life insurance (COLI) or bank-owned life insurance (BOLI).

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Amount of advances from Federal Home Loan Bank (FHLBank) maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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-Topic 470

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-Paragraph 1

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Fair value portion of borrowing from Federal Home Loan Bank (FHLBank).

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Amount of Federal Home Loan Bank (FHLB) and Federal Reserve Bank stock.

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Amount after other than temporary impairment (OTTI) accretion, of investments in debt securities classified as held-to-maturity.

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Fair value of investments in debt securities classified as held-to-maturity.

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Amount of interest payable on debt, including, but not limited to, trade payables.

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Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

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Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

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Amount classified as mortgage loans attributable to disposal group held for sale or disposed of. Excludes loans and leases covered under loss sharing agreements and loans classified as debt securities.

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Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

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The carrying amount as of the balance sheet date for the aggregate of other miscellaneous borrowings owed by the reporting entity.

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Disclosures about Fair Value Measurements (Fair Value of Financial Instruments) (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014	Mar. 31, 2014	Dec. 31, 2013
FINANCIAL ASSETS: Carrying Value
Cash and cash equivalents	$ 30,718	$ 32,872	$ 29,869	$ 30,066
Investment securities - HTM	19,477us-gaap_HeldToMaturitySecurities	19,840us-gaap_HeldToMaturitySecurities
Regulatory stock	5,626	6,173
Loans held for sale	3,575us-gaap_LoansHeldForSaleMortgages	5,051us-gaap_LoansHeldForSaleMortgages
Loans, net of allowance for loan loss and unearned income	840,708	817,457
Accrued interest income receivable	3,300	3,127
Bank owned life insurance	37,388us-gaap_BankOwnedLifeInsurance	37,417us-gaap_BankOwnedLifeInsurance
Cash and cash equivalents	30,718	32,872
Investment securities - AFS	122,533us-gaap_AvailableForSaleSecurities	127,110us-gaap_AvailableForSaleSecurities
Investment securities - HTM	20,013	20,213
Regulatory stock	5,626	6,173
Loans held for sale	3,675	5,127
Loans, net of allowance for loan loss and unearned income	845,904	819,935
Accrued interest income receivable	3,300	3,127
Bank owned life insurance	37,388	37,417
FINANCIAL LIABILITIES: Carrying Value
Deposits with no stated maturities	587,825asrv_DepositsWithNoStatedMaturities	568,625asrv_DepositsWithNoStatedMaturities
Deposits with stated maturities	304,851asrv_DepositsWithStatedMaturities	301,256asrv_DepositsWithStatedMaturities
Short-term borrowings	27,219	38,880
All other borrowings	57,085us-gaap_OtherBorrowings	55,085us-gaap_OtherBorrowings
Accrued interest payable	1,545	1,706
Deposits with no stated maturities	587,825	568,625
Deposits with stated maturities	307,634	304,744
Short-term borrowings	27,219	38,880
All other borrowings	61,695	59,256
Accrued interest payable	1,545	1,706
Level 1 [Member]
FINANCIAL ASSETS: Carrying Value
Cash and cash equivalents	30,718	32,872
Investment securities - AFS
Investment securities - HTM
Regulatory stock	5,626	6,173
Loans held for sale	3,675	5,127
Loans, net of allowance for loan loss and unearned income
Accrued interest income receivable	3,300	3,127
Bank owned life insurance	37,388	37,417
FINANCIAL LIABILITIES: Carrying Value
Deposits with no stated maturities	587,825	568,625
Deposits with stated maturities
Short-term borrowings	27,219	38,880
All other borrowings
Accrued interest payable	1,545	1,706
Level 2 [Member]
FINANCIAL ASSETS: Carrying Value
Cash and cash equivalents
Investment securities - AFS	122,533	127,110
Investment securities - HTM	17,031	17,241
Regulatory stock
Loans held for sale
Loans, net of allowance for loan loss and unearned income
Accrued interest income receivable
Bank owned life insurance
FINANCIAL LIABILITIES: Carrying Value
Deposits with no stated maturities
Deposits with stated maturities
Short-term borrowings
All other borrowings
Accrued interest payable
Level 3 [Member]
FINANCIAL ASSETS: Carrying Value
Cash and cash equivalents
Investment securities - AFS
Investment securities - HTM	2,982	2,972
Regulatory stock
Loans held for sale
Loans, net of allowance for loan loss and unearned income	845,904	819,935
Accrued interest income receivable
Bank owned life insurance
FINANCIAL LIABILITIES: Carrying Value
Deposits with no stated maturities
Deposits with stated maturities	307,634	304,744
Short-term borrowings
All other borrowings	61,695	59,256
Accrued interest payable