Unconsolidated Entities - Summary of Investments (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Schedule Of Equity Method Investments [Line Items]
Other ventures	$ 4,230,429	$ 4,755,620
Unconsolidated Co-Investment Ventures [Member]
Schedule Of Equity Method Investments [Line Items]
Other ventures	4,057,524	4,585,427
Other Joint Ventures [Member]
Schedule Of Equity Method Investments [Line Items]
Other ventures	$ 172,905	$ 170,193