FHLBP Advances and Short-Term Borrowed Funds (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Repurchase agreement amount, percentage	102.00%
Repurchase agreements and repurchase-to-maturity transactions	$ 12,023	$ 11,889
Federal Home Loan Bank, Advances, Branch of FHLB Bank, Interest Rate	1.44%	1.13%
Federal Home Loan Bank, Advances, Branch of FHLB Bank, Amount of Advances	$ 79,013	$ 55,332
Federal Home Loan Bank Of Pittsburgh [Member]
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Line of credit facility maximum borrowing capacity	$ 456,900
Short-Term Borrowing Maximum Period	364 days
Loans used as collateral		648,000
Federal Home Loan Bank, Advances, Branch of FHLB Bank, Interest Rate	70.51%
Maturity Overnight and Continuous [Member]
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Repurchase agreements and repurchase-to-maturity transactions	$ 12,023	11,889
State and Municipal Tax-Exempt [Member] \| Maturity Overnight and Continuous [Member]
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Repurchase agreements and repurchase-to-maturity transactions	12,300	$ 12,100
Federal Funds Purchased [Member]
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Line of credit facility maximum borrowing capacity	60,000
Letter of Credit [Member] \| Federal Home Loan Bank Of Pittsburgh [Member]
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Line of credit facility maximum borrowing capacity	$ 65,000

Percentage of Repurchase Agreement amount sold

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- Definition

Short-Term Borrowing Maximum Period

+ References

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- Definition

Amount of advances from the Federal Home Loan Bank (FHLB).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6479118&loc=d3e64650-112822

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- Definition

Discloses the single interest rate [if] applicable to the advances from the Federal Home Loan Bank, by branch, as of the Balance Sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=75038535&loc=d3e64711-112823

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-Section 45
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-URI http://asc.fasb.org/extlink&oid=6479118&loc=d3e64650-112822

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Carrying amount as of the balance sheet date of loans that have been pledged as collateral for borrowings. If the secured party has the right by contract or custom to sell or re-pledge the collateral, then the debtor reclassifies that asset and report that asset in its statement of financial position separately from other assets not so encumbered.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=66007379&loc=d3e113888-111728

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- Definition

Carrying value, as of the balance sheet date, of securities sold under agreements to repurchase where the transferor maintains effective control over the assets, accounting for them as secured debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(m)(1)(i))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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