Income Taxes - Reconciliation of Income Tax Expense (Benefit) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Tax Expense (Benefit), Continuing Operations, Income Tax Reconciliation [Abstract]
Tax at federal statutory rate									$ 167,294	$ 36,400	$ 20,031
State, net of federal benefit									2,466	1,635	622
Contingent liabilities									18	948	903
Share-based compensation									(819)	(8,131)	(4,019)
FDII									(402)	0	0
Research and development credits									(879)	(2,758)	(2,821)
Change in uncertain tax positions									441	858	1,308
Rate change for changes in federal or state law									(210)	178	32,429
Change in valuation allowance									(1,193)	(4,225)	(4,169)
Expired NOLs and credits									0	3,054	0
Change in derivatives									0	615	0
Other									621	1,435	391
Income tax expense from continuing operations	$ (810)	$ (4,620)	$ (3,609)	$ 176,376	$ (14,307)	$ 11,864	$ 22,419	$ 10,033	$ 167,337	$ 30,009	$ 44,675