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STOCK COMPENSATION EXPENSE, Assumptions (Details) (USD $)
 12 Months Ended
Dec. 31, 2014
Dec. 31, 2013
Dec. 31, 2012
Assumptions used in the Black-Scholes option-pricing model [Abstract]      
Risk-free interest rate (in hundredths) 2.78%pfbi_ShareBasedCompensationArrangementFairValueAssumptionsRiskFreeInterestRate 1.96%pfbi_ShareBasedCompensationArrangementFairValueAssumptionsRiskFreeInterestRate 2.31%pfbi_ShareBasedCompensationArrangementFairValueAssumptionsRiskFreeInterestRate
Expected option life (yrs) 10 years 10 years 10 years
Expected stock price volatility (in hundredths) 31.19%pfbi_ShareBasedCompensationArrangementFairValueAssumptionsExpectedVolatilityRate 35.24%pfbi_ShareBasedCompensationArrangementFairValueAssumptionsExpectedVolatilityRate 34.93%pfbi_ShareBasedCompensationArrangementFairValueAssumptionsExpectedVolatilityRate
Dividend yield (in hundredths) 3.33%pfbi_ShareBasedCompensationArrangementFairValueAssumptionsExpectedDividendRate 3.86%pfbi_ShareBasedCompensationArrangementFairValueAssumptionsExpectedDividendRate 2.68%pfbi_ShareBasedCompensationArrangementFairValueAssumptionsExpectedDividendRate
Weighted average fair value of options granted during the year (in dollars per share) $ 3.74pfbi_ShareBasedCompensationArrangementOptionsGrantsInPeriodWeightedAverageGrantDateFairValue $ 2.85pfbi_ShareBasedCompensationArrangementOptionsGrantsInPeriodWeightedAverageGrantDateFairValue $ 2.34pfbi_ShareBasedCompensationArrangementOptionsGrantsInPeriodWeightedAverageGrantDateFairValue