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Stock-Based Compensation - Additional Information (Details) - USD ($)
1 Months Ended 12 Months Ended
Apr. 21, 2015
Apr. 22, 2014
Apr. 24, 2013
Apr. 22, 2008
Apr. 30, 2015
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Mar. 13, 2013
Mar. 12, 2013
Feb. 27, 2008
Feb. 26, 2008
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                        
Granted (in shares)             0 0        
Stock-based compensation expense not recognized by employer             $ 0 $ 0        
Stock Options                        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                        
Granted (in shares)           0 0 0        
Intrinsic value of options exercised               $ 100,000        
Unvested Stock Options                        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                        
Amount of nonvested stock options           0 0 0        
Unrecognized compensation costs related to unvested options           $ 0            
Restricted Stock Units                        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                        
Allocated share-based compensation expense           $ 1,600,000 $ 2,400,000 $ 3,800,000        
Restricted stock units awarded (in shares)           12,589 31,099 72,291        
Vesting period               3 years        
Unrecognized stock-based compensation costs           $ 2,700,000 $ 4,400,000 $ 7,300,000        
Vested (in shares)           (150,073) (145,421) (90,965)        
Number of performance-based shares forfeited (in shares)           16,500 34,729 0        
Weighted average remaining recognition period of unrecognized stock-based compensation costs           3 years 9 months 18 days 4 years 4 years        
Performance Shares                        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                        
Allocated share-based compensation expense           $ 1,300,000 $ 300,000          
Restricted stock units awarded (in shares)           125,392 89,117          
Vesting period         3 years 3 years            
Vested (in shares)             (9,687)          
Number of performance-based shares forfeited (in shares)           24,056 0          
Weighted average remaining recognition period of unrecognized stock-based compensation costs           1 year 7 months 6 days            
Performance Shares | Maximum                        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                        
Unrecognized compensation costs related to unvested options           $ 5,400,000 $ 5,638,000          
Long-term incentive plan                        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                        
Maximum number of shares of common stock available for awards before amendment                   2,175,000   2,000,000
Maximum number of shares of common stock available for awards                 2,975,000   2,175,000  
Plan expiration period       20 years                
Shares remaining available for awards           370,420            
Granted (in shares)           0            
Stock-based compensation expense not recognized by employer           $ 0            
Long-term incentive plan | Stock Options                        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                        
Historical volatility period of common stock used to estimate the fair value of each option grant           90 days            
Directors | Long-term incentive plan                        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                        
Vested stock grants to directors (in shares) 32,357 19,336 21,949                  
Directors | Long-term incentive plan | Vested stock grants                        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                        
Allocated share-based compensation expense $ 700,000 $ 500,000 $ 500,000     $ 700,000 $ 500,000 $ 500,000        
Executive Officer | Restricted Stock Units                        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                        
Restricted stock units awarded (in shares)           3,963 31,099 68,044        
Vesting period           3 years 5 years 5 years        
Additional restricted stock units authorized (in shares)               4,247        
Executive Officer | Performance Shares                        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                        
Allocated share-based compensation expense           $ 100,000 $ 200,000          
Vesting period           3 years 3 years          
Vested (in shares)           (6,915) (9,687)