XML 19 R42.htm IDEA: XBRL DOCUMENT v2.4.1.9
STOCK COMPENSATION EXPENSE, Assumptions (Details) (USD $)
3 Months Ended
Mar. 31, 2015
Mar. 31, 2014
Assumptions used in the black-scholes option-pricing model [Abstract]    
Risk-free interest rate (in hundredths) 1.41%pfbi_ShareBasedCompensationArrangementFairValueAssumptionsRiskFreeInterestRate 2.78%pfbi_ShareBasedCompensationArrangementFairValueAssumptionsRiskFreeInterestRate
Expected option life (yrs) 5 years 10 years
Expected stock price volatility (in hundredths) 17.20%pfbi_ShareBasedCompensationArrangementFairValueAssumptionsExpectedVolatilityRate 31.19%pfbi_ShareBasedCompensationArrangementFairValueAssumptionsExpectedVolatilityRate
Dividend yield (in hundredths) 3.53%pfbi_ShareBasedCompensationArrangementFairValueAssumptionsExpectedDividendRate 3.33%pfbi_ShareBasedCompensationArrangementFairValueAssumptionsExpectedDividendRate
Weighted average fair value of options granted during the year (in dollars per share) $ 1.37pfbi_ShareBasedCompensationArrangementOptionsGrantsInPeriodWeightedAverageGrantDateFairValue $ 3.74pfbi_ShareBasedCompensationArrangementOptionsGrantsInPeriodWeightedAverageGrantDateFairValue