Annual report pursuant to Section 13 and 15(d)

Stock Based Compensation - A Summary of the Values of Options Granted and Exercised (Detail)

v2.4.1.9
Stock Based Compensation - A Summary of the Values of Options Granted and Exercised (Detail) (USD $)
In Thousands, except Per Share data, unless otherwise specified
12 Months Ended
Dec. 31, 2014
Dec. 31, 2013
Dec. 31, 2012
Summary of the values of options granted and exercised      
Number of Shares Underlying Options, Granted 1,118us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross 1,836us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross 1,024us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross
Weighted average grant date fair value - ($/share) $ 2.43us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue $ 2.45us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue $ 3.49us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue
Weighted average exercise price - ($/share) $ 5.04us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice $ 4.25us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice $ 4.62us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice
Options exercised (thousands) 1,128us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised 877us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised 759us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised
Total intrinsic value of options exercised - ($thousands) $ 4,120us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue $ 1,201us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue $ 3,267us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue