Carrying value of available for sale held to maturity and federal home loan bank.

No definition available.

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- Definition

Consolidated investment securities portfolio modified, years.

+ References

No definition available.

+ Details

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- Definition

The gain realized from the sale, exchange, redemption, or retirement of securities, not separately or otherwise categorized as trading, available-for-sale, or held-to-maturity.

+ References

No definition available.

+ Details

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- Details

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- Definition

The loss realized from the sale, exchange, redemption, or retirement of securities, not separately or otherwise categorized as trading, available-for-sale, or held-to-maturity.

+ References

No definition available.

+ Details

Name:	asrv_LossOnSaleOfSecurities
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Balance Type:	credit
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- Definition

Percentage of investment securities portfolio rated.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
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- Details

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- Definition

Disclosure regarding factors used to determine that the impairment of securities categorized as held-to-maturity where cost exceeds fair value is not an other than temporary impairment (OTTI). This item contains disclosure of the number of investment positions in the held-to-maturity investments determined to be temporarily impaired.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 6

-Subparagraph (b)(3)

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27290-111563

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Balance Type:	na
Period Type:	instant

- Definition

The cash inflow associated with the sale of debt and equity securities classified as available-for-sale securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Investing Activities

-URI http://asc.fasb.org/extlink&oid=6516133

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 45

-Paragraph 11

-URI http://asc.fasb.org/extlink&oid=6871852&loc=d3e26853-111562

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 12

-Subparagraph (a),(b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3179-108585

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Investment Securities (Narrative) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
	Jun. 30, 2014	Jun. 30, 2014	Jun. 30, 2013	Dec. 31, 2013
Investment [Line Items]
Gross investment gains	$ 120	$ 182	$ 71
Gross investment losses		5
Investment Securities:
Consolidated investment securities portfolio modified, years		3 years 1 month 10 days
Proceeds from sales of investment securities - available for sale	2,500	5,242	1,218
Book value of securities available for sale and held to maturity	$ 121,224	$ 121,224		$ 110,780
Positions considered temporarily impaired	44	44
Standard & Poor's, AAA Rating [Member]
Investment [Line Items]
Portfolio rated	87.50%	87.50%		89.00%
Standard & Poor's, A Rating [Member]
Investment [Line Items]
Portfolio rated	2.00%	2.00%