Long-Term Debt - Components Of Net Interest Expense (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Debt Disclosure [Abstract]
Interest expense	$ 6,097	$ 8,007	$ 18,152	$ 22,580
Capitalized interest				(1,182)
Interest income	(169)	(409)	(252)	(991)
Net interest expense	$ 5,928	$ 7,598	$ 17,900	$ 20,407