Income Taxes from Continuing Operations - Income Tax Provision (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Current
Federal	$ 78,806	$ 107,818	$ 116,375
State	1,706	11,247	11,113
Foreign	89	0	0
Total	80,601	119,065	127,488
Deferred
Federal	(105,006)	(26,377)	(41,477)
State	(9,785)	(4,325)	(2,620)
Foreign	(458)	(1,306)	(2,033)
Total	(115,249)	(32,008)	(46,130)
Total
Federal	(26,200)	81,441	74,898
State	(8,079)	6,922	8,493
Foreign	(369)	(1,306)	(2,033)
Income tax provision	$ (34,648)	$ 87,057	$ 81,358