Corporate Indebtedness-Interest (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Debt Disclosure [Abstract]
Interest expense	$ 83,536	$ 86,045	$ 248,905	$ 248,986
Interest income	(563)	(386)	(1,485)	(1,197)
Interest expense, net	82,973	85,659	247,420	247,789
Interest capitalized	$ 2,828	$ 3,360	$ 9,191	$ 8,892