Quarterly report pursuant to Section 13 or 15(d)

Share-Based Compensation - Additional Information (Detail)

v2.4.1.9
Share-Based Compensation - Additional Information (Detail) (USD $)
3 Months Ended
Mar. 31, 2015
Mar. 31, 2014
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]    
Share-based compensation expense $ 528,000us-gaap_ShareBasedCompensation $ 605,000us-gaap_ShareBasedCompensation
Related tax benefits on non-qualified stock options $ 30,000us-gaap_EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense $ 112,000us-gaap_EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense
Number of shares, stock options exercised 19,581us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised 15,195us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised
Restricted stock awards, continuous employment period for vesting of grant Three to five years