Income Taxes - Income Tax Provision (Benefit) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Current:
U.S. - Federal	$ (12,810)	$ 0	$ 0
U.S. - State	20	97	330
Total current	(12,790)	97	330
Deferred:
Ireland	0	(1,256)	0
U.S. - Federal	680	(4,093)	(19,503)
U.S. - State	0	(104)	1,280
Total deferred	680	(5,453)	(18,223)
Income tax benefit	$ (12,110)	$ (5,356)	$ (17,893)