Unconsolidated Entities - Earnings and Fee Revenue From Co-Investment Ventures (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Schedule Of Equity Method Investments [Line Items]
Earnings from unconsolidated entities, net	$ 159,262	$ 134,288	$ 97,220
Strategic capital revenue	210,362	219,871	179,472
Unconsolidated Co-Investment Ventures [Member]
Schedule Of Equity Method Investments [Line Items]
Earnings from unconsolidated entities, net	155,402	131,048	94,654
Total strategic capital revenue and other income	207,608	218,350	177,185
Strategic capital revenue	215,075	223,774	181,192
Unconsolidated Co-Investment Ventures [Member] | Development Management and Other Revenue [Member]
Schedule Of Equity Method Investments [Line Items]
Total strategic capital revenue and other income	7,467	5,424	4,007
Unconsolidated Co-Investment Ventures [Member] | Americas [Member]
Schedule Of Equity Method Investments [Line Items]
Earnings from unconsolidated entities, net	35,966	8,596	21,724
Total strategic capital revenue and other income	59,480	94,354	70,642
Unconsolidated Co-Investment Ventures [Member] | Europe [Member]
Schedule Of Equity Method Investments [Line Items]
Earnings from unconsolidated entities, net	106,656	108,430	63,839
Total strategic capital revenue and other income	112,675	86,487	63,794
Unconsolidated Co-Investment Ventures [Member] | Asia [Member]
Schedule Of Equity Method Investments [Line Items]
Earnings from unconsolidated entities, net	12,780	14,022	9,091
Total strategic capital revenue and other income	$ 35,453	$ 37,509	$ 42,749