Corporate Indebtedness - Schedule of Consolidated Interest Expense, Excluding Capitalized Interest (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Interest expense
Interest expense before capitalized interest	$ 244,788	$ 284,649	$ 348,062
Interest capitalized	(34,162)	(26,020)	(24,067)
Interest income	(1,957)	(1,584)	(2,796)
Interest expense, net	$ 208,669	$ 257,045	$ 321,199