Annual report pursuant to Section 13 and 15(d)

Stock-Based Compensation - Narratives (Details)

v3.8.0.1
Stock-Based Compensation - Narratives (Details) - USD ($)
8 Months Ended 12 Months Ended 17 Months Ended
Oct. 02, 2017
May 04, 2016
Jan. 13, 2015
Dec. 31, 2016
Dec. 31, 2017
Dec. 31, 2016
Dec. 31, 2015
Sep. 30, 2017
Oct. 03, 2017
May 03, 2016
Dec. 31, 2014
PQ Holdings, Eco Services                      
Share-based Compensation Arrangement by Share-based Payment Award                      
Stock awards transferred as consideration   $ 1,400,000                  
Stock Option                      
Share-based Compensation Arrangement by Share-based Payment Award                      
Stock based compensation expense not yet recognized (options)         $ 3,909,000            
Period for which unrecognized compensation will be recognized         2 years 3 months 25 days            
Restricted Stock                      
Share-based Compensation Arrangement by Share-based Payment Award                      
Nonvested units (shares)   2,444,070   2,482,932 2,096,637 2,482,932          
Granted (shares) 21,067     266,955 51,907            
Stock compensation         $ 8,799,000 $ 7,029,000 $ 2,256,000        
Tax benefit from exercise of stock options         $ 3,345,000 2,662,000 0        
Period for which unrecognized compensation will be recognized         2 years 6 months            
Stock based compensation expense not yet recognized (other than options)         $ 27,544,000            
Performance Awards                      
Share-based Compensation Arrangement by Share-based Payment Award                      
Stock compensation         0 $ 0 $ 0        
Compensation costs not yet recognized         $ 16,472,000            
Performance Awards | Exit Event Exceeding Threshold                      
Share-based Compensation Arrangement by Share-based Payment Award                      
Awards vesting rights percentage             100.00%        
Incentive Unit Agreement | Stock Awards | Class B units                      
Share-based Compensation Arrangement by Share-based Payment Award                      
Stock options granted (shares)     14,419       14,419        
Granted (weighted average exercise price, usd per share)     $ 1,000       $ 1,000        
Options outstanding (shares)             25,093     25,093 11,367
Fair value of options granted (usd per share)         $ 448            
Expected term (in years)             7 years        
Expected volatility             40.27%        
Risk-free interest rate             2.02%        
Expected dividend yield             0.00%        
Service period         4 years            
Weighted average exercise price (usd per share)             $ 1,000     $ 1,000 $ 1,000
Incentive Unit Agreement | Stock Awards | Class B units | Employee                      
Share-based Compensation Arrangement by Share-based Payment Award                      
Options outstanding (shares)             10,674        
Incentive Unit Agreement | Stock Awards | Class B units | Employee | Time based                      
Share-based Compensation Arrangement by Share-based Payment Award                      
Awards vesting rights percentage             50.00%        
Incentive Unit Agreement | Stock Awards | Class B units | Employee | Performance based                      
Share-based Compensation Arrangement by Share-based Payment Award                      
Awards vesting rights percentage             50.00%        
Incentive Unit Agreement | Stock Awards | Class B units | Employee | Annual Vesting as of Dec 1, 2015                      
Share-based Compensation Arrangement by Share-based Payment Award                      
Awards vesting rights percentage             25.00%        
Incentive Unit Agreement | Stock Awards | Class B units | Directors and affiliates                      
Share-based Compensation Arrangement by Share-based Payment Award                      
Options outstanding (shares)             14,419        
2016 Plan | Stock Option                      
Share-based Compensation Arrangement by Share-based Payment Award                      
Stock options granted (shares) 621,747             7,644,518      
Options outstanding (shares)   1,378,302                  
Shares authorized (shares)   8,017,038                  
Weighted average exercise price (usd per share)   $ 8.04                  
Accelerated compensation cost   $ 1,174,000                  
Expiration period 10 years         10 years          
2017 Omnibus Plan | Stock Option                      
Share-based Compensation Arrangement by Share-based Payment Award                      
Stock options granted (shares)       538,908 1,051,496            
Granted (weighted average exercise price, usd per share)       $ 8.05 $ 13.70            
Options outstanding (shares)   1,738,527   1,798,438 2,715,170 1,798,438          
Expected term (in years)         5 years 10 months 6 days 5 years          
Expected volatility         34.85% 45.79%          
Risk-free interest rate         2.00% 1.54%          
Expected dividend yield         0.00% 0.00%          
Shares reserved for issuance (shares)                 7,344,000    
Number of shares available for grant (shares)         5,427,526       372,520    
Weighted average exercise price (usd per share)   $ 7.80   $ 7.96 $ 10.18 $ 7.96