Pension Plan (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Change in benefit obligation [Roll Forward]
Benefit obligation at beginning of year	$ 5,656	$ 6,262
Service cost	0us-gaap_DefinedBenefitPlanServiceCost	0us-gaap_DefinedBenefitPlanServiceCost
Interest cost	278us-gaap_DefinedBenefitPlanInterestCost	252us-gaap_DefinedBenefitPlanInterestCost
Benefits paid	(298)us-gaap_DefinedBenefitPlanBenefitsPaid	(480)us-gaap_DefinedBenefitPlanBenefitsPaid
Actuarial loss	1,468	(378)
Benefit obligation at end of year	7,104	5,656
Change in plan assets [Roll Forward]
Fair value of plan assets at beginning of year	5,322	5,168
Actual return on plan assets	244	634
Employer contribution	0	0
Benefits paid	(298)us-gaap_DefinedBenefitPlanBenefitsPaid	(480)us-gaap_DefinedBenefitPlanBenefitsPaid
Fair value of plan assets at end of year	5,268	5,322
Funded Status at end of year	(1,836)	(334)
Amounts recognized in the consolidated balance sheets at December 31 [Abstract]
Accrued pension liability	(1,836)	(334)
Amounts recognized in other comprehensive income (loss) [Abstract]
Loss	3,681	2,345
Deferred taxes	(1,252)	(797)
Defined Benefit Pension Plan, Net Amount Recognized in Other Comprehensive Income	2,429	1,548
Accumulated benefit obligation	7,104	5,656
Assumptions used to determine the benefit obligations at December 31 [Abstract]
Discount rate (in hundredths)	3.73%	4.90%
Components of net periodic pension cost [Abstract]
Interest cost	278us-gaap_DefinedBenefitPlanInterestCost	252us-gaap_DefinedBenefitPlanInterestCost
Expected return on plan assets	(362)	(351)
Amortization of unrecognized loss	251	303
Preliminary Net periodic pension cost	167opof_PreliminaryNetPeriodPensionCost	204opof_PreliminaryNetPeriodPensionCost
Settlement loss	0	0
Net Periodic Pension Plan Cost	167	204
Components of other amounts recognized in other comprehensive income [Abstract]
Net actuarial loss	1,587	(661)
Settlement loss	0	0
Amortization of unrecognized loss	(251)	(303)
Defined Benefit Plan Other Amount Recognized in Other Comprehensive Income	1,336	(964)
Total recognized in net periodic benefit cost and other comprehensive income	1,503	(760)
Estimated net loss for the pension plan that will be amortized next year	393
Weighted-average assumptions used to determine net periodic pension cost [Abstract]
Discount rate (in hundredths)	4.90%	4.10%
Expected long-term rate of return on plan assets (in hundredths)	7.00%	7.00%
Fair value of pension plan assets by asset category [Abstract]
Fair Value of pension plan assets	5,268	5,322
Estimated future benefit payments, which reflect expected future service [Abstract]
Next 12 Months	216
2 Years	221
3 Years	261
4 Years	283
5 Years	293
Thereafter	1,936
Total	3,210
401(K) PLAN [Abstract]
Employer matching contribution (in hundredths)	100.00%
Employee contribution (in hundredths)	4.00%
Profit sharing contributions vesting period	6 years
Profit sharing contributions	527	642
Equities [Member]
Defined Benefit Plan, Assets, Target Allocations [Abstract]
Target allocation percentage (in hundredths)	55.00%
Fixed income [Member]
Defined Benefit Plan, Assets, Target Allocations [Abstract]
Target allocation percentage (in hundredths)	40.00%
Cash [Member]
Defined Benefit Plan, Assets, Target Allocations [Abstract]
Target allocation percentage (in hundredths)	5.00%
Equity mutual funds [Member]
Defined Benefit Plan, Assets, Target Allocations [Abstract]
Target allocation percentage (in hundredths)	1.00%
Money market funds [Member]
Change in plan assets [Roll Forward]
Fair value of plan assets at end of year	310	240
Fair value of pension plan assets by asset category [Abstract]
Fair Value of pension plan assets	310	240
U.S. Government securities [Member]
Change in plan assets [Roll Forward]
Fair value of plan assets at end of year		75
Fair value of pension plan assets by asset category [Abstract]
Fair Value of pension plan assets		75
Mutual Funds [Member]
Change in plan assets [Roll Forward]
Fair value of plan assets at end of year	73	2,999
Fair value of pension plan assets by asset category [Abstract]
Fair Value of pension plan assets	73	2,999
Common Stock [Member]
Change in plan assets [Roll Forward]
Fair value of plan assets at end of year	2,847	2,008
Fair value of pension plan assets by asset category [Abstract]
Fair Value of pension plan assets	2,847	2,008
Commodities Investment [Member]
Defined Benefit Plan, Assets, Target Allocations [Abstract]
Target allocation percentage (in hundredths)	1.00%
Corporate bonds [Member]
Change in plan assets [Roll Forward]
Fair value of plan assets at end of year	2,038	5,322
Fair value of pension plan assets by asset category [Abstract]
Fair Value of pension plan assets	2,038	5,322
Level 1 [Member]
Change in plan assets [Roll Forward]
Fair value of plan assets at end of year	3,230
Fair value of pension plan assets by asset category [Abstract]
Fair Value of pension plan assets	3,230
Level 1 [Member] \| Money market funds [Member]
Change in plan assets [Roll Forward]
Fair value of plan assets at end of year	310	240
Fair value of pension plan assets by asset category [Abstract]
Fair Value of pension plan assets	310	240
Level 1 [Member] \| U.S. Government securities [Member]
Change in plan assets [Roll Forward]
Fair value of plan assets at end of year		75
Fair value of pension plan assets by asset category [Abstract]
Fair Value of pension plan assets		75
Level 1 [Member] \| Mutual Funds [Member]
Change in plan assets [Roll Forward]
Fair value of plan assets at end of year	73	2,999
Fair value of pension plan assets by asset category [Abstract]
Fair Value of pension plan assets	73	2,999
Level 1 [Member] \| Common Stock [Member]
Change in plan assets [Roll Forward]
Fair value of plan assets at end of year	2,847	0
Fair value of pension plan assets by asset category [Abstract]
Fair Value of pension plan assets	2,847	0
Level 1 [Member] \| Corporate bonds [Member]
Change in plan assets [Roll Forward]
Fair value of plan assets at end of year	0	3,314
Fair value of pension plan assets by asset category [Abstract]
Fair Value of pension plan assets	0	3,314
Level 2 [Member]
Change in plan assets [Roll Forward]
Fair value of plan assets at end of year	2,038
Fair value of pension plan assets by asset category [Abstract]
Fair Value of pension plan assets	2,038
Level 2 [Member] \| Money market funds [Member]
Change in plan assets [Roll Forward]
Fair value of plan assets at end of year	0	0
Fair value of pension plan assets by asset category [Abstract]
Fair Value of pension plan assets	0	0
Level 2 [Member] \| U.S. Government securities [Member]
Change in plan assets [Roll Forward]
Fair value of plan assets at end of year		0
Fair value of pension plan assets by asset category [Abstract]
Fair Value of pension plan assets		0
Level 2 [Member] \| Mutual Funds [Member]
Change in plan assets [Roll Forward]
Fair value of plan assets at end of year	0	0
Fair value of pension plan assets by asset category [Abstract]
Fair Value of pension plan assets	0	0
Level 2 [Member] \| Common Stock [Member]
Change in plan assets [Roll Forward]
Fair value of plan assets at end of year	0	2,008
Fair value of pension plan assets by asset category [Abstract]
Fair Value of pension plan assets	0	2,008
Level 2 [Member] \| Corporate bonds [Member]
Change in plan assets [Roll Forward]
Fair value of plan assets at end of year	2,038	2,008
Fair value of pension plan assets by asset category [Abstract]
Fair Value of pension plan assets	2,038	2,008
Level 3 [Member]
Change in plan assets [Roll Forward]
Fair value of plan assets at end of year	0
Fair value of pension plan assets by asset category [Abstract]
Fair Value of pension plan assets	0
Level 3 [Member] \| Money market funds [Member]
Change in plan assets [Roll Forward]
Fair value of plan assets at end of year	0	0
Fair value of pension plan assets by asset category [Abstract]
Fair Value of pension plan assets	0	0
Level 3 [Member] \| U.S. Government securities [Member]
Change in plan assets [Roll Forward]
Fair value of plan assets at end of year		0
Fair value of pension plan assets by asset category [Abstract]
Fair Value of pension plan assets		0
Level 3 [Member] \| Mutual Funds [Member]
Change in plan assets [Roll Forward]
Fair value of plan assets at end of year	0	0
Fair value of pension plan assets by asset category [Abstract]
Fair Value of pension plan assets	0	0
Level 3 [Member] \| Common Stock [Member]
Change in plan assets [Roll Forward]
Fair value of plan assets at end of year	0	0
Fair value of pension plan assets by asset category [Abstract]
Fair Value of pension plan assets	0	0
Level 3 [Member] \| Corporate bonds [Member]
Change in plan assets [Roll Forward]
Fair value of plan assets at end of year	0	0
Fair value of pension plan assets by asset category [Abstract]
Fair Value of pension plan assets	$ 0	$ 0

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Net of tax and reclassifications amount of pension and other postretirement benefit plans (gain) loss included in accumulated other comprehensive income (loss).

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Total amount of benefits expected to be paid from a defined benefit plan.

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Total loss (gain) related to other amounts recognized in other comprehensive income.

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Net loss included in other amounts recognized in other comprehensive income during the period.

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Deferred tax effect of the increase (decrease) in the value of the projected benefit obligation and the (increase) decrease in the value of the plan assets resulting from experience different from that assumed or from a change in an actuarial assumption that has not been recognized in net periodic benefit cost.

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Subtotal of components of net periodic pension cost.

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Vesting period of contributions made under profit sharing plan to the employees.

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The total amount of net periodic benefit cost for defined benefit plans for the period. Periodic benefit costs include the following components: service cost, interest cost, expected return on plan assets, gain (loss), prior service cost or credit, transition asset or obligation, and gain (loss) due to settlements or curtailments and other amounts recognized in other comprehensive income.

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For defined benefit pension plans, the actuarial present value of benefits (whether vested or nonvested) attributed by the pension benefit formula to employee service rendered before a specified date and based on employee service and compensation (if applicable) before that date. The accumulated benefit obligation differs from the projected benefit obligation in that it includes no assumption about future compensation levels. For plans with flat-benefit or nonpay-related pension benefit formulas, the accumulated benefit obligation and the projected benefit obligation are the same.

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-Name Accounting Standards Codification

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The difference between fair value of plan assets at the end of the period and the fair value at the beginning of the period, adjusted for contributions and payments of benefits during the period, and after adjusting for taxes and other expenses, as applicable.

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Amount of gain (loss) related to change in benefit obligation resulting from changes in actuarial assumptions, for example, but not limited to, interest, mortality, employee turnover, salary, and temporary deviation from the substantive plan.

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The amount of gains or losses recognized in net periodic benefit cost.

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The aggregate net amount recognized in the balance sheet associated with the defined benefit plan(s). Will normally be the same as the Defined Benefit Plan, Funded Status of Plan, Total.

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Amount included in accumulated other comprehensive income (AOCI) expected to be recognized as components of net periodic benefit cost for the fiscal year that follows the most recent annual statement of financial position, including gain (loss), prior service cost (credit), and transition asset (obligation).

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No definition available.

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The interest rate used to adjust for the time value of money for the plan.

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The interest rate used to adjust for the time value of money.

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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.

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1) For defined benefit pension plans, the benefit obligation is the projected benefit obligation, which is the actuarial present value as of a date of all benefits attributed by the pension benefit formula to employee service rendered prior to that date. 2) For other postretirement defined benefit plans, the benefit obligation is the accumulated postretirement benefit obligation, which is the actuarial present value of benefits attributed to employee service rendered to a particular date.

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The amount of payments made for which participants are entitled under a pension plan, including pension benefits, death benefits, and benefits due on termination of employment. Also includes payments made under a postretirement benefit plan, including prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services. This item represents a periodic decrease to the plan obligations and a decrease to plan assets.

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The increase in the fair value of plan assets from contributions made by the employer.

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Amount of benefits from a defined benefit plan expected to be paid in the five fiscal years after the fifth 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.

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Amount of benefits from a defined benefit plan expected to be paid 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.

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Amount of benefits from a defined benefit plan expected to be paid in the fifth 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.

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Amount of benefits from a defined benefit plan expected to be paid in the fourth 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.

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Amount of benefits from a defined benefit plan expected to be paid in the third 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.

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Amount of benefits from a defined benefit plan expected to be paid 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.

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An amount calculated as a basis for determining the extent of delayed recognition of the effects of changes in the fair value of assets. The expected return on plan assets is determined based on the expected long-term rate of return on plan assets and the market-related value of plan assets.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 30

-Glossary Expected Return on Plan Assets

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-Name Accounting Standards Codification

-Topic 715

-SubTopic 60

-Glossary Expected Return on Plan Assets

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-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (h)(3)

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Assets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those non-benefit obligations may be considered as reductions of plan assets.

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The funded status is measured as the difference between the fair value of plan assets and the benefit obligation. Will normally be the same as the net Defined Benefit Plan, Amounts Recognized in Balance Sheet, Total.

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The increase in a defined benefit pension plan's projected benefit obligation or a defined benefit postretirement plan's accumulated postretirement benefit obligation due to the passage of time.

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Amount of net gain (loss) recognized in net periodic benefit cost due to settlements and curtailments. Curtailments result from an event that significantly reduces the expected years of future service of present employees or eliminates for a significant number of employees the accrual of defined benefits for some or all of their future services. Settlements result from an irrevocable action that relieves the employer (or the plan) of primary responsibility for a benefit obligation and eliminates significant risks related to the obligation and the assets used to effect the settlement. Examples of transactions that constitute a settlement include, but are not limited to, lump-sum cash payments to plan participants in exchange for their rights to receive specified benefits and purchasing nonparticipating annuity contracts to cover vested benefits.

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The actuarial present value of benefits attributed by the pension benefit formula to services rendered by employees during the period. The portion of the expected postretirement benefit obligation attributed to employee service during the period. The service cost component is a portion of the benefit obligation and is unaffected by the funded status of the plan.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

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-Name Accounting Standards Codification

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

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- Definition

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

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 70

-Section 50

-Paragraph 1

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Percentage employer matches of the employee's percentage contribution matched.

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Maximum percentage of employee gross pay the employee may contribute to a defined contribution plan.

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Amount before tax and reclassification adjustments of (increase) decrease in accumulated other comprehensive (income) loss related to pension and other postretirement benefit plans.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

-Section 45

-Paragraph 10A

-Subparagraph (i-k)

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