Accounts Payable and Accrued Expenses (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Payables and Accruals [Abstract]
Accrued capital expenditures	$ 74,008	$ 71,769
Accounts payable and accrued expenses	28,516	32,509
Interest rate swap agreements liability	0	436
Accrued interest payable	3,642	5,687
Due to affiliated companies	664	448
Total accounts payable and accrued expenses	$ 106,830	$ 110,849