Income Taxes - Components of Income Tax Expense (Benefit) Table (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Current income tax expense (benefit)
Federal income tax expense (benefit)	$ 5,550	$ (79,264)	$ (9,207)
State income tax expense (benefit)	313	(850)	2,422
Total current income tax expense (benefit)	5,863	(80,114)	(6,785)
Deferred income tax expense (benefit)
Federal income tax expense (benefit)	2,782	133,044	(55,835)
State income tax expense (benefit)	4,827	6,004	2,697
Total deferred income tax expense (benefit)	7,609	139,048	(53,138)
Total income tax expense (benefit)	$ 13,472	$ 58,934	$ (59,923)