Long-Term Debt - Components Of Net Interest Expense (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Debt Disclosure [Abstract]
Interest expense	$ 7,179	$ 8,045	$ 14,573	$ 15,941
Interest income	(116)	(675)	(582)	(1,433)
Capitalized interest	0	(5,165)	(1,182)	(10,205)
Net interest expense	$ 7,063	$ 2,205	$ 12,809	$ 4,303