CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) (in thousands) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Statement of Comprehensive Income [Abstract]
Net income (loss)		$ (187,001)	$ 508,407	$ (160,843)
Other comprehensive income, net of tax:
Pension liability adjustment	[1]	1,061	4,378	767
Total other comprehensive income, net of tax		1,061	4,378	767
Total comprehensive income (loss)		$ (185,940)	$ 512,785	$ (160,076)

[1] ⁽¹⁾  Please refer to Note 8 – Pension Benefits for additional discussion on the pension liability adjustment.