Short Term and Long Term Borrowings (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Debt Instrument [Line Items]
Overnight repurchase agreements	37,404opof_OvernightRepurchaseAgreements	$ 31,175opof_OvernightRepurchaseAgreements
U.S. Treasury demand notes	0	0
Number of customer relationships	3opof_NumberOfCustomerRelationships
Major customer relationship repurchase agreements maximum percentage (in hundredths)	5.00%
Outstanding balance	29,695
Percentage of repurchase agreements (in hundredths)	78.52%
1 - 4 family residential real estate pledged loans	76,341us-gaap_LoansPledgedAsCollateral
Federal Funds Purchased, Amount of Available, Unused Funds	50,000
Federal Home Loan Bank, Advances, General Debt Obligations, Amount of Available, Unused Funds	231,507
Fixed Rate [Abstract]
Due in one year or less	5,000	0
Due after one year through five years	25,000	25,000
Total long-term debt	30,000	25,000
Total [Abstract]
Due in one year or less	5,000	0
Due after one year through two years	25,000	25,000
Total long-term debt	30,000	$ 25,000
Weighted Avg Rate [Abstract]
Due in one year or less (in hundredths)	0.26%	0.00%
Due after three years through four years (in hundredths)	4.83%
Due after four years through five years (in hundredths)		4.83%
Total long-term debt (in hundredths)	4.07%	4.83%
Maximum [Member]
Debt Instrument [Line Items]
Overnight repurchase agreements maturity period	4 days
Minimum [Member]
Debt Instrument [Line Items]
Overnight repurchase agreements maturity period	1 day

Amount of credit lines available from other banks, at the federal funds rate.

No definition available.

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- Definition

The amount borrowed by a bank, at the federal funds rate, from another bank to meet its reserve requirements, and the carrying amount as of the balance sheet date for the aggregate of other miscellaneous borrowings owed by the reporting entity.

+ References

No definition available.

+ Details

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- Definition

The cutoff above which repurchase agreement relationships are considered to be significant, expressed as a percent of total repurchase agreements.

+ References

No definition available.

+ Details

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- Definition

Percent of repurchase agreements attributable to significant relationships.

+ References

No definition available.

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- Definition

The total balance in repurchase agreements attributable to significant relationships.

+ References

No definition available.

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- Definition

Number of single external customer relationships that account for 5 percent of the entity's total repurchase agreements.

+ References

No definition available.

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- Definition

The carrying value as of the balance sheet date of securities that an institution sells and agrees to repurchase (the identical or substantially the same securities) as a seller-borrower at a specified date (generally within one to four days) for a specified price, also known as a repurchase agreement, or repo. Repos involve obligations of the federal government or its agencies.

+ References

No definition available.

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- Definition

Overnight repurchase agreements maturity term in days.

+ References

No definition available.

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- Definition

Amount of borrowings as of the balance sheet date from the Federal Home Loan Bank, which are primarily used to cover shortages in the required reserve balance and liquidity shortages.

+ References

+ Details

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- Definition

Describes the weighted average interest rate applicable to the specific advances from the Federal Home Loan Bank, by branch, as of the Balance Sheet date.

+ References

+ Details

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- Definition

Amount of advances or credit lines available 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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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.13(3)(a))

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 13

-Subparagraph 3(a)

-Article 9

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- Definition

The weighted average interest rate applicable to the Federal Home Loan Bank advances which are due from four to five years of the Balance Sheet date.

+ References

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- Definition

The weighted average interest rate applicable to the Federal Home Loan Bank advances which are due within one year of the Balance Sheet date.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.13(3)(a))

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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

-Publisher SEC

-Name Industry Guide

-Number 3

-Section VII.3

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- Definition

The weighted average interest rate applicable to the Federal Home Loan Bank advances which are due from three to four years of the Balance Sheet date.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.14)

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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-Publisher SEC

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-Number 3

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-Paragraph 3

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- Definition

Amount of Federal Home Loan Bank (FHLB) advances which have fixed interest.

+ References

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- Definition

Amount of Federal Home Loan Bank (FHLB) advances which have fixed interest rates maturing between the next fiscal year and the fifth fiscal year following the latest fiscal year.

+ References

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- Definition

Amount of Federal Home Loan Bank (FHLB) advances which have fixed interest rates maturing in the next fiscal year following the latest fiscal year.

+ References

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- Definition

Amount of advances from Federal Home Loan Bank (FHLBank) maturing in the second 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.

+ References

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- Definition

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.

+ References

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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 310

-SubTopic 10

-Section 50

-Paragraph 5

-URI http://asc.fasb.org/extlink&oid=35738203&loc=d3e5086-111524

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-Topic 860

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