Annual report pursuant to Section 13 and 15(d)

Schedule I - Condensed Statements of Operations (Details)

v3.8.0.1
Schedule I - Condensed Statements of Operations (Details) - USD ($)
$ in Thousands
3 Months Ended 12 Months Ended
Dec. 31, 2017
Sep. 30, 2017
Jun. 30, 2017
Mar. 31, 2017
Dec. 31, 2016
Sep. 30, 2016
Jun. 30, 2016
Mar. 31, 2016
Dec. 31, 2017
Dec. 31, 2016
Dec. 31, 2015
Condensed Financial Statements, Captions                      
Stock compensation                 $ 8,799 $ 5,432 $ 2,256
Net income (loss) attributable to PQ Group Holdings Inc. $ 65,011 $ (3,345) $ (1,609) $ (2,454) $ 10,664 $ (10,017) $ (77,262) $ (3,131) 57,603 (79,746) 11,427
Other comprehensive income (loss), net of tax:                      
Comprehensive income (loss) attributable to PQ Group Holdings Inc.                 115,625 (134,105) $ 12,075
Parent Company                      
Condensed Financial Statements, Captions                      
Stock compensation                 8,799 7,029  
Equity in income (loss) of subsidiaries                 66,402 (72,717)  
Net income (loss) attributable to PQ Group Holdings Inc.                 57,603 (79,746)  
Other comprehensive income (loss), net of tax:                      
Pension and postretirement benefits                 (101) 6,865  
Net (loss) gain from hedging activities                 (3,590) 4,557  
Foreign currency translation                 61,713 (65,781)  
Total other comprehensive income (loss)                 58,022 (54,359)  
Comprehensive income (loss) attributable to PQ Group Holdings Inc.                 $ 115,625 $ (134,105)