CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) $ in Thousands	Total	Common Stock	Paid-in Capital	Retained Earnings	Accumulated Other Comprehensive Income	Treasury Stock
Beginning Balance at Dec. 31, 2016	$ 295,969		$ 173,879	$ 122,078	$ 12
Beginning Balance (in shares) at Dec. 31, 2016		47,105,744
Isle common stock exchanged at merger	574,811		574,811
Isle common stock exchanged at merger (in shares)		28,468,182
Issuance of restricted stock units	6,322		6,322
Issuance of restricted stock units (in shares)		1,070,552
Other	(487)			(487)
Net income	73,380			73,380
Other comprehensive (loss) income	67				67
Exercise of stock options	$ 2,900		2,900
Exercise of stock options (in shares)	1,185,745	1,185,745
Shares withheld related to net share settlement of stock awards	$ (11,365)		(11,365)
Shares withheld related to net share settlement of stock awards (in shares)		(1,004,257)
Ending Balance at Dec. 31, 2017	941,597		746,547	194,971	79
Ending Balance (in shares) at Dec. 31, 2017		76,825,966
Issuance of restricted stock units	13,084	$ 1	13,083
Issuance of restricted stock units (in shares)		848,737
Purchase of treasury shares	(9,131)	$ (9,100)				$ (9,131)
Purchase of treasury shares, (in shares)		223,823				223,823
Net income	95,235			95,235
Other comprehensive (loss) income	(78)				(78)
Exercise of stock options	$ 154		154
Exercise of stock options (in shares)	120,120	67,336
Shares withheld related to net share settlement of stock awards	$ (11,708)		(11,708)
Shares withheld related to net share settlement of stock awards (in shares)		(303,150)
Ending Balance at Dec. 31, 2018	1,029,153	$ 1	748,076	290,206	1	$ (9,131)
Ending Balance (in shares) at Dec. 31, 2018		77,438,889				223,823
Cumulative change in accounting principle, net of tax	(4,744)			(4,744)
Issuance of restricted stock units	19,719		19,719
Issuance of restricted stock units (in shares)		540,753
Purchase of treasury shares, (in shares)		0
Net income	81,001			81,001
Other comprehensive (loss) income	$ 376				376
Exercise of stock options (in shares)	0
Shares withheld related to net share settlement of stock awards	$ (8,248)		(8,248)
Shares withheld related to net share settlement of stock awards (in shares)		(186,702)
Ending Balance at Dec. 31, 2019	$ 1,117,257	$ 1	$ 759,547	$ 366,463	$ 377	$ (9,131)
Ending Balance (in shares) at Dec. 31, 2019		77,792,940				223,823