Income Taxes - Income Tax Rate Reconciliation (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Computed “expected” tax provision	$ (92,018)	$ (20,719)	$ 94,955
Change in income taxes resulting from:
State income taxes, net of Federal income tax	(11,667)	(537)	4,501
Change in state income tax rate, net of Federal income tax	(16)	(4,714)	0
Foreign income tax (benefit) provision	(1,658)	2,206	1,580
Deduction for domestic production activities	0	(2,527)	(7,280)
Stock compensation	2,480	(1,316)	(11,395)
R&D tax credits	(750)	(1,200)	(825)
Nondeductible acquisition fees	(1,165)	1,974	39
Interest and penalties from Federal audit	7,935	15,650	0
Federal rate change	(3,027)	(26,902)	0
Discrete adjustments to prior year	570	1,561	0
162(m) Officers Compensation Limitation	1,483	0	0
Other expense, net	934	1,201	2,564
Valuation allowance change	60,626	675	2,918
Income tax (benefit) provision	$ (36,273)	$ (34,648)	$ 87,057