Annual report pursuant to Section 13 and 15(d)

Share-based Compensation - Unrecognized Share-Based Compensation Expense (Detail)

v2.4.1.9
Share-based Compensation - Unrecognized Share-Based Compensation Expense (Detail) (USD $)
In Thousands, unless otherwise specified
 12 Months Ended
Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]  
Unrecognized Expense $ 3,958us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized
Average Expected Recognition Period 2 years 1 month 6 days
Stock option awards [Member]  
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]  
Unrecognized Expense 1,349us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized
/ us-gaap_AwardTypeAxis
= us-gaap_EmployeeStockOptionMember
Average Expected Recognition Period 1 year 9 months 18 days
Restricted stock awards [Member]  
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]  
Unrecognized Expense $ 2,609us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized
/ us-gaap_AwardTypeAxis
= us-gaap_RestrictedStockMember
Average Expected Recognition Period 2 years 2 months 12 days