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Stock-Based Compensation and Stock Awards - Performance Unit Awards - Additional Information (Detail) - Performance Unit Awards
$ / shares in Units, $ in Millions
12 Months Ended
Dec. 31, 2019
USD ($)
component
$ / shares
shares
Dec. 31, 2018
USD ($)
$ / shares
shares
Dec. 31, 2017
USD ($)
shares
Oct. 28, 2019
$ / shares
Oct. 28, 2018
$ / shares
Oct. 28, 2017
$ / shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Share price (in dollars per share) | $ / shares $ 44.53 $ 43.09   $ 48.47 $ 54.62 $ 54.64
Percentage of grant share price (as a percentage) 108.90% 126.80% 131.70%      
Number of components companies in the Philadelphia Oil Service Index | component 15          
Performance unit compensation expense $ 9.6 $ 4.2 $ 5.4      
Income tax benefit recognized 1.9 $ 0.4 $ 0.8      
Unrecognized compensation expense related to share based compensation $ 8.3          
Period of recognition for unrecognized compensation expense related to nonvested stock options (in years) 2 years 1 month 6 days          
Anti-dilutive performance share units (in shares) | shares 14,596 169,000 160,000      
Minimum            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Participants earning under the term (as a percentage) 0.00%          
Maximum            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Participants earning under the term (as a percentage) 200.00%