Fair Value Measurements (Details 3) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2014	Dec. 31, 2013
Fair Value of nonrecourse mortgage debt and notes payable (including land held for divestiture debt), bank revolving credit facility and senior and subordinated debt
Carrying Value	$ 4,716,396	$ 5,279,506
Fair Value	5,061,598	5,442,542
Fixed Rate Debt [Member]
Fair Value of nonrecourse mortgage debt and notes payable (including land held for divestiture debt), bank revolving credit facility and senior and subordinated debt
Carrying Value	2,892,316	3,281,337
Fair Value	3,241,230	3,488,406
Variable Rate Debt [Member]
Fair Value of nonrecourse mortgage debt and notes payable (including land held for divestiture debt), bank revolving credit facility and senior and subordinated debt
Carrying Value	1,824,080	1,998,169
Fair Value	$ 1,820,368	$ 1,954,136