Quarterly report pursuant to Section 13 or 15(d)

Stock-Based Compensation Plans - Additional Information (Detail)

v2.4.0.8
Stock-Based Compensation Plans - Additional Information (Detail) (USD $)
In Thousands, except Share data, unless otherwise specified
3 Months Ended
Mar. 31, 2014
Mar. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Stock based compensation $ 717 $ 436
SARs Liability frozen value date Mar. 31, 2013  
Notes receivable from employees [Member]
   
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Notes issued, interest rate   5.00%
Notes issued, interest rate   6.00%
Notes issued, payment date   Apr. 15, 2016
Pre-IPO [Member]
   
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Terms of Issued Options One year or less  
Stock options exercised   750
Number of stock option redemption or cancelations   0
Stock based compensation   $ 400
Pre-IPO [Member] | Minimum [Member]
   
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Restricted common stock issued, vesting period   3 years
Pre-IPO [Member] | Maximum [Member]
   
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Restricted common stock issued, vesting period   5 years
Restricted Stock [Member] | Prior to IPO Stock-based Compensation Award Program [Member]
   
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Unrecognized stock-based compensation expenses recognition period 4 years  
Sales restriction lapse percentage for restricted stock 20.00%  
Sales restriction period for restricted stock 5 years  
Percentage of shares of stock released from resale restriction upon consummation of change of control 100.00%  
Deferred stock units [Member]
   
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
DSU settlement into actual stock issued term 5 years  
DSU Settlement to Common Stock Percentage 20.00%  
Employee termination age 67  
Percentage of deferred stock units settled 100.00%  
Percentage of shares of deferred stock units released from resale restriction 100.00%