v2.4.0.8
Organization and Basis of Presentation - Additional Information (Detail) (USD $)
In Thousands, except Share data, unless otherwise specified
 1 Months Ended 9 Months Ended 12 Months Ended
Aug. 13, 2013
Jul. 26, 2013
Sep. 30, 2013
Dec. 31, 2011
Subsidiary
Dec. 31, 2012
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]          
Number of subsidiaries acquired       3  
Reverse stock split ratio   1-for-1.75      
Reverse stock split ratio   0.57143      
Aggregate proceeds from the IPO     $ 168,801    
Shares of common stock 79,705,130        
Number of authorized shares of common stock 200,000,000   200,000,000 155,000,000 160,000,000
Number of authorized shares of preferred stock 25,000,000        
IPO [Member]
          
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]          
Shares of common stock 11,499,998        
Price per share of common stock $ 16.00        
Aggregate proceeds from the IPO 168,300        
Underwriting discounts and commissions 12,900        
Offering Expense paid 2,800        
Capitalized expenses $ 2,300        
Exercise of Overallotment Option by Underwriters [Member]
          
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]          
Shares of common stock 1,499,999