Income Taxes - Reconciliation of Income Tax (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Amount
Tax expense (benefit) at statutory rate	$ (78,648)	$ 7,435	$ 70,928
State income taxes	(17,159)	1,844	9,620
Corporate owned life insurance	(85)	(933)	0
Nondeductible executive compensation	566	371	1,130
Impairment	35,109	0	0
Change in valuation allowances	17,355	5,851	1,080
Share-based compensation	1,073	2,995	0
Domestic production activities deduction	0	(244)	(4,393)
Transition tax on unrepatriated foreign earnings	0	2,106	0
Tax reform revaluation of deferred taxes	0	(45,840)	0
Other	(494)	236	3,669
Total income tax expense (benefit)	$ (42,283)	$ (26,179)	$ 82,034
Percentage
Tax expense (benefit) at statutory rate (as a percent)	21.00%	35.00%	35.00%
State income taxes (as a percent)	4.60%	8.70%	4.80%
Corporate owned life insurance (as a percent)	(0.00%)	(4.40%)	(0.00%)
Nondeductible executive compensation (as a percent)	(0.10%)	1.80%	0.60%
Impairment (as a percent)	(9.40%)	0.00%	0.00%
Change in valuation allowances (as a percent)	(4.60%)	27.50%	0.50%
Share-based compensation (as a percent)	(0.30%)	14.10%	0.00%
Domestic production activities deduction (as a percent)	(0.00%)	(1.20%)	(2.20%)
Deemed repatriation of foreign earnings (as a percent)	0.00%	9.90%	0.00%
Tax reform revaluation of deferred taxes (as a percent)	0.00%	(215.80%)	0.00%
Other (as a percent)	0.10%	1.20%	1.80%
Total (as a percent)	11.30%	(123.20%)	40.50%