CONSOLIDATED STATEMENTS OF COMPREHENSIVE (LOSS) INCOME - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
CONSOLIDATED STATEMENTS OF COMPREHENSIVE (LOSS) INCOME
NET (LOSS) INCOME	$ (212,192)	$ (87,111)	$ 175,402
OTHER COMPREHENSIVE (LOSS) INCOME, NET OF TAXES:
Pension adjustment	5,727	(5,030)	(1,408)
Foreign currency translation	(210)	553	(621)
COMPREHENSIVE (LOSS) INCOME	$ (206,675)	$ (91,588)	$ 173,373