CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) $ in Thousands	Total	Common Stock	Paid-in Capital	Retained Earnings	Accumulated Other Comprehensive Income	Treasury Stock
Beginning balance (in shares) at Dec. 31, 2018		77,438,889				223,823
Beginning balance at Dec. 31, 2018	$ 1,029,153	$ 1	$ 748,076	$ 290,206	$ 1	$ (9,131)
Issuance of restricted stock units (in shares)		330,641
Issuance of restricted stock units	4,948		4,948
Net income (loss)	38,229			38,229
Cumulative change in accounting principle, net of tax	(4,744)			(4,744)
Shares withheld related to net share settlement of stock awards (in shares)		(106,542)
Shares withheld related to net share settlement of stock awards	(4,322)		(4,322)
Ending balance (in shares) at Mar. 31, 2019		77,662,988				223,823
Ending balance at Mar. 31, 2019	1,063,264	$ 1	748,702	323,691	1	$ (9,131)
Beginning balance (in shares) at Dec. 31, 2018		77,438,889				223,823
Beginning balance at Dec. 31, 2018	1,029,153	$ 1	748,076	290,206	1	$ (9,131)
Net income (loss)	57,165
Ending balance (in shares) at Jun. 30, 2019		77,766,924				223,823
Ending balance at Jun. 30, 2019	1,085,519	$ 1	752,021	342,627	1	$ (9,131)
Beginning balance (in shares) at Mar. 31, 2019		77,662,988				223,823
Beginning balance at Mar. 31, 2019	1,063,264	$ 1	748,702	323,691	1	$ (9,131)
Issuance of restricted stock units (in shares)		169,248
Issuance of restricted stock units	6,509		6,509
Net income (loss)	18,936			18,936
Shares withheld related to net share settlement of stock awards (in shares)		(65,312)
Shares withheld related to net share settlement of stock awards	(3,190)		(3,190)
Ending balance (in shares) at Jun. 30, 2019		77,766,924				223,823
Ending balance at Jun. 30, 2019	1,085,519	$ 1	752,021	342,627	1	$ (9,131)
Beginning balance (in shares) at Dec. 31, 2019		77,792,940				223,823
Beginning balance at Dec. 31, 2019	1,117,257	$ 1	759,547	366,463	377	$ (9,131)
Issuance of restricted stock units (in shares)		356,367
Issuance of restricted stock units	5,742		5,742
Net income (loss)	(175,638)			(175,638)
Shares withheld related to net share settlement of stock awards (in shares)		(122,590)
Shares withheld related to net share settlement of stock awards	(7,152)		(7,152)
Ending balance (in shares) at Mar. 31, 2020		78,026,717				223,823
Ending balance at Mar. 31, 2020	940,209	$ 1	758,137	190,825	377	$ (9,131)
Beginning balance (in shares) at Dec. 31, 2019		77,792,940				223,823
Beginning balance at Dec. 31, 2019	1,117,257	$ 1	759,547	366,463	377	$ (9,131)
Net income (loss)	$ (275,634)
Exercise of stock options (in shares)	15,300
Ending balance (in shares) at Jun. 30, 2020		98,789,501				223,823
Ending balance at Jun. 30, 2020	$ 1,616,449	$ 1	1,534,373	90,829	377	$ (9,131)
Beginning balance (in shares) at Mar. 31, 2020		78,026,717				223,823
Beginning balance at Mar. 31, 2020	940,209	$ 1	758,137	190,825	377	$ (9,131)
Issuance of restricted stock units (in shares)		71,887
Issuance of restricted stock units	4,229		4,229
Issuance of common stock, net (in shares)		20,700,000
Issuance of common stock, net	772,392		772,392
Net income (loss)	(99,996)			(99,996)
Exercise of stock options (in shares)		15,300
Exercise of stock options	62		62
Shares withheld related to net share settlement of stock awards (in shares)		(24,403)
Shares withheld related to net share settlement of stock awards	(447)		(447)
Ending balance (in shares) at Jun. 30, 2020		98,789,501				223,823
Ending balance at Jun. 30, 2020	$ 1,616,449	$ 1	$ 1,534,373	$ 90,829	$ 377	$ (9,131)