Agreement and Plan of Merger (Narrative) (Details) - Jun. 30, 2015 - FNBPA Bancorp, Inc. [Member] $ / shares in Units, $ in Millions	USD ($) $ / shares
Business Acquisition [Line Items]
Date of acquisition agreement	Jun. 26, 2015
Scenario, Plan [Member]
Business Acquisition [Line Items]
Per share price of acquiree's share for "Cash Selection"	$ 50.34
Number of Juniata's shares for each FNBPA share for "Stock Selection"	2.7813
Cash transaction value of acquisition \| $	$ 13.2
Minimum [Member] \| Scenario, Plan [Member]
Business Acquisition [Line Items]
Percentage of aggregate consideration paid in cash	15.00%
Maximum [Member] \| Scenario, Plan [Member]
Business Acquisition [Line Items]
Percentage of aggregate consideration paid in cash	25.00%

Business acquisition, percentage of aggregate consideration paid in cash.

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- Definition

Business acquisition share conversion ratio.

+ References

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- Definition

Date when the business acquisition agreement was executed, in CCYY-MM-DD format.

+ References

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- Definition

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.

+ References

No definition available.

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- Definition

Price of a single share of a number of saleable stocks paid or offered to be paid in a business combination.

+ References

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- Definition

The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

+ 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 230

-SubTopic 10

-Section 45

-Paragraph 13

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3213-108585

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