v3.3.1.900
Share-Based Compensation - Additional Information (Detail) - USD ($)
12 Months Ended
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Maximum term of stock option 10 years    
Amendment effective date Jun. 02, 2015    
Share-based compensation expense $ 7,954,000 $ 8,247,000 $ 5,901,000
Shares subject to stock options, granted 0 0 0
Shares subject to stock options, shares exercisable 38,525    
Weighted average exercise price, outstanding $ 12.00    
Weighted average remaining contractual term, outstanding 1 year 10 months 10 days    
Number of stock options exercised 0 0  
Intrinsic value of the options exercised     $ 35,000
Tax benefit recognized related to the stock option exercises     0
Service period 3 years 6 months    
Current fiscal year employer matching contribution description We make a matching contribution equal to 100% of each pre-tax dollar contributed by the participant on the first 3% of eligible compensation and 50% on the next 2% of eligible compensation    
Contributions to employee benefit plan $ 404,000 $ 310,000 279,000
Primary [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Employer matching contribution, percentage 100.00%    
Secondary [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Employer matching contribution, percentage 50.00%    
Non Employee Director [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Share-based compensation expense $ 735,000 749,000 630,000
2007 Plan [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
The maximum number of common stock 3,625,000    
Forfeiture Benefit Adjustments Member [Member] | Executive Officers [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Forfeited stock awards   $ 1,100,000 $ 1,000,000
Nonvested Shares [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Shares grant 1,278,329 992,919 377,379
Average grant date fair value $ 6,200,000 $ 14,400,000 $ 8,600,000
Unrecognized compensation expense related to nonvested shares $ 7,900,000    
Nonvested outstanding weighted average remaining service period 3 years    
Nonvested Shares [Member] | Executive Officers [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Additional shares grant 724,249 245,157 183,672
Additional share grant fair value $ 4,500,000 $ 4,500,000 $ 4,400,000
Total Shareholder Return Performance Stock Awards [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Subsequent restricted share award 550,272    
Fair market value of shares subject to performance conditions $ 300,000    
Cash Settled Performance Shares [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Subsequent restricted share award 1,100,543    
Fair market value of shares subject to performance conditions $ 1,000,000