CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Statement of Comprehensive Income [Abstract]
Net income	$ 509	$ 3,441
Other comprehensive income (loss), net of tax:
Pension and postretirement benefits	(15)	(30)
Net loss from hedging activities	(529)	(1,552)
Foreign currency translation	(46,355)	7,167
Total other comprehensive income (loss)	(46,899)	5,585
Comprehensive income (loss)	(46,390)	9,026
Less: Comprehensive income (loss) attributable to noncontrolling interests	(3,203)	605
Comprehensive income (loss) attributable to PQ Group Holdings Inc.	$ (43,187)	$ 8,421

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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