CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) (UNAUDITED) (in thousands) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ (98,292)	$ 42,234	$ (599,439)	$ (84,946)
Other comprehensive income, net of tax:
Pension liability adjustment	1,195	190	1,573	572
Total other comprehensive income, net of tax	1,195	190	1,573	572
Total comprehensive income (loss)	$ (97,097)	$ 42,424	$ (597,866)	$ (84,374)