Condensed Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Net income (loss)	$ (43,767)	$ 3,988	$ (48,309)	$ 1,027
Other comprehensive income (loss):
Pension and other post-retirement benefit adjustments, net of tax	1,510	2,879	2,287	3,634
Change in fair value of derivative instruments, net of tax	(4,830)	472	(7,884)	1,942
Foreign currency translation adjustments, net of tax	(271)	(7,392)	(297)	(3,059)
Other comprehensive income (loss), net of tax	(3,591)	(4,041)	(5,894)	2,517
Comprehensive income (loss)	$ (47,358)	$ (53)	$ (54,203)	$ 3,544