Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Statement of Comprehensive Income [Abstract]
Net loss	$ (3,125)	$ 80,277	$ 17,913	$ 191,842
Other comprehensive (loss) income, net of tax:
Foreign currency translation, net of tax of $(655), $(3,474), $(1,078) and $(3,474), respectively	(27,962)	(2,475)	(6,584)	(30,334)
Net unrealized gain on cash flow hedges, net of tax of $51, $174, $27 and $474, respectively	149	522	78	773
Net unrealized gain (loss) on investment securities, net of tax of $509, $(417), $2,573 and $(2,230), respectively	1,487	(1,218)	7,516	(6,514)
Amortization of pension and postretirement costs, net of tax benefits of $2,633, $2,399, $7,406 and $7,766, respectively	7,552	8,810	21,499	24,850
Other comprehensive (loss) income, net of tax	(18,774)	5,639	22,509	(11,225)
Comprehensive (loss) income	$ (21,899)	$ 85,916	$ 40,422	$ 180,617