Earnings per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Numerator
Net income (loss)	$ (27,828)	$ 56,076
Denominator
Weighted-average shares outstanding, basic (in shares)	68,521	68,380
Effect of dilutive stock awards (in shares)	0	136
Adjusted weighted-average shares outstanding, diluted (in shares)	68,521	68,516
Earnings (loss) per share
Basic earnings (loss) per common share (in dollars per share)	$ (0.41)	$ 0.82
Diluted earnings (loss) per common share (in dollars per share)	$ (0.41)	$ 0.82
Anti-dilutive weighted average shares (in shares)	482	159
Income tax benefit	$ 46,766	$ (16,005)
CARES Act
Earnings (loss) per share
Basic earnings (loss) per common share (in dollars per share)	$ 0.45
Diluted earnings (loss) per common share (in dollars per share)	$ 0.45
Federal | CARES Act
Earnings (loss) per share
Income tax benefit	$ 31,100