Interest Expense (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Interest Expense [Abstract]
Interest expense before capitalized interest	$ 18,339	$ 20,431	$ 35,040	$ 43,308
Amortization of deferred financing costs	779	714	1,398	1,878
Net unrealized (gain) loss on derivative financial instruments not designated as cash flow hedges	17		(30)	48
Capitalized interest	(3,365)	(8,038)	(8,633)	(14,953)
Interest Expense	$ 15,770	$ 13,107	$ 27,775	$ 30,281