Defined Benefit Plan, Maximum Percent Of Assets Comprised Of Entity Common Stock.

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- Definition

Defined Benefit Plan, Minimum Number Of Annual Employee Hours.

+ References

No definition available.

+ Details

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- Definition

Defined Benefit Plan, Vesting Period.

+ References

No definition available.

+ Details

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- Definition

Defined Contribution Plan, Amount Of Entity Common Stock And Securities Held.

+ References

No definition available.

+ Details

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- Definition

Maximum percentage of union employee gross pay, by the terms of the plan, that the employer may contribute to a defined contribution plan.

+ References

No definition available.

+ Details

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- Definition

The amounts in accumulated other comprehensive income related to gains and losses that are not recognized immediately and are expected to be recognized as components of net periodic benefit cost over the next fiscal year that follows the most recent annual statement of financial position presented.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (s)

-URI http://asc.fasb.org/extlink&oid=21915506&loc=d3e1928-114920

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 158

-Paragraph 7

-Subparagraph d

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 132R

-Paragraph 5

-Subparagraph s

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

The amounts in accumulated other comprehensive income related to prior service cost or credit expected to be recognized as components of net periodic benefit cost over the next fiscal year that follows the most recent annual statement of financial position presented.

+ References

+ Details

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- Definition

The amounts in accumulated other comprehensive income related to transition assets (obligations), origination from the adoption of FAS 87 and 106, expected to be recognized as components of net periodic benefit cost over the next fiscal year that follows the most recent annual statement of financial position presented.

+ References

+ Details

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- Definition

The amount of employer securities or securities of parties related to the employer that are included in plan assets.

+ References

+ Details

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- Definition

An assumption as to the rate of return on plan assets reflecting the average rate of earnings expected on the funds invested or to be invested to provide for the benefits included in the benefit obligation.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (k)(3)

-URI http://asc.fasb.org/extlink&oid=21915506&loc=d3e1928-114920

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 87

-Paragraph 264

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 132R

-Paragraph 5

-Subparagraph j

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 30

-Glossary Expected Long-Term Rate of Return on Plan Assets

-URI http://asc.fasb.org/extlink&oid=6512013

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- Definition

The employer's best estimate, as soon as it can be reasonably determined, of contributions expected to be paid to the plan during the next fiscal year beginning after the date of the latest statement of financial position. Estimated contributions may be presented in the aggregate combining (1) contributions required by funding regulations or laws, (2) discretionary contributions, and (3) noncash contributions.

+ References

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- Definition

Target allocation of investments of this type to total plan assets presented on a weighted average basis.

+ References

+ Details

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- Definition

Target allocation maximum percentage of investments of this type to total plan assets presented on a weighted average basis.

+ References

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- Definition

Target allocation minimum percentage of investments of this type to total plan assets presented on a weighted average basis.

+ References

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- Definition

The amount of the cost recognized during the period for defined contribution plans.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 70

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6414718&loc=d3e28014-114942

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 132R

-Paragraph 11

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

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- Definition

Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan.

+ References

No definition available.

+ Details

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- Definition

Maximum percentage of employee gross pay, by the terms of the plan, that the employer may contribute to a defined contribution plan.

+ References

No definition available.

+ Details

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EMPLOYEE BENEFIT PLANS (Narrative) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
401(k) PLAN:
Contributions to charged to operations	$ 277	229
Employer match percentage	2.00%
Maximum percent of salary	1.00%
Allowance For Loan Losses String	4.00%
AmeriServ Financial, Inc. common stock and Trust Preferred securities held	914
Pension Plans [Member]
PENSION PLANS:
Minimum number of annual hours	1000 hours
Vesting term	5 years
AmeriServ Financial, Inc. common stock held	626
Maximum percent of plan assets comprised of AmeriServ Financial, Inc. common stock	10.00%
Estimated net loss that will be amortized from accumulated other comprehensive income (loss)	1,363
Estimated prior service cost that will be amortized from accumulated other comprehensive income (loss)	(20)
Estimated transition asset that will be amortized from accumulated other comprehensive income (loss)	8
Expected return on plan assets	8.00%	8.00%	8.00%
Expected contribution in 2013	$ 2,500
Pension Plans [Member] \| Domestic Equities [Member]
PENSION PLANS:
Target allocation	60.00%
Target allocation, minimum	50.00%
Target allocation, maximum	60.00%
Pension Plans [Member] \| Fixed Income Securities [Member]
PENSION PLANS:
Target allocation, minimum	40.00%
Target allocation, maximum	50.00%