Business Segments - Segment Reporting, Reconciliation of Revenues, Operating Income and Assets (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Segment Reporting Information [Line Items]
Total revenues	$ 517,557	$ 504,419	$ 503,110	$ 480,875	$ 456,777	$ 462,141	$ 310,326	$ 222,084	$ 2,005,961	$ 1,451,327	$ 840,152
Consolidated net earnings (loss)									(30,472)	(157,938)	(1,270,453)
General and administrative expenses									(228,068)	(195,161)	(165,981)
Merger, acquisition and other integration expenses									(80,676)	(140,495)	0
Impairment of real estate properties									(252,914)	(21,237)	(736,612)
Depreciation and amortization									(739,981)	(552,849)	(294,867)
Earnings from unconsolidated entities net									31,676	59,935	23,678
Interest expense									(507,484)	(468,072)	(461,166)
Impairment of goodwill and other assets									(16,135)	(126,432)	(412,745)
Interest and other income, net									22,878	12,008	15,847
Gains on acquisitions and dispositions of investments in real estate, net									305,607	111,684	28,488
Foreign currency and derivative gains (losses), net									(20,497)	41,172	(11,081)
Gain (loss) on early extinguishment of debt, net									(14,114)	258	(201,486)
Loss before income taxes									(89,622)	(265,414)	(1,631,986)
Total assets	27,310,145				27,723,912				27,310,145	27,723,912
Investments in and advances to other unconsolidated entities	2,195,782				2,857,755				2,195,782	2,857,755
Notes receivable backed by real estate	188,000				322,834				188,000	322,834
Assets held for sale	26,027				444,850				26,027	444,850
Cash and cash equivalents	100,810				176,072				100,810	176,072	37,634	34,362
Other assets	188,473				176,699				188,473	176,699
Total reconciling items	2,699,092				3,978,210				2,699,092	3,978,210
Real estate operations [Member]
Segment Reporting Information [Line Items]
Total revenues									1,879,182	1,313,708	717,626
Consolidated net earnings (loss)									1,347,127	931,118	502,072
Total assets	24,519,306				23,630,994				24,519,306	23,630,994
Private capital [Member]
Segment Reporting Information [Line Items]
Total revenues									126,779	137,619	122,526
Consolidated net earnings (loss)									62,959	82,657	81,867
Total assets	91,747				114,708				91,747	114,708
Operating Segments [Member]
Segment Reporting Information [Line Items]
Consolidated net earnings (loss)									1,410,086	1,013,775	583,939
Total assets	24,611,053				23,745,702				24,611,053	23,745,702
Reconciling Items [Member]
Segment Reporting Information [Line Items]
Consolidated net earnings (loss)									(1,499,708)	(1,279,189)	(2,215,925)
Americas [Member] | Real estate operations [Member]
Segment Reporting Information [Line Items]
Total revenues									1,211,462	842,845	556,389
Consolidated net earnings (loss)									841,319	584,081	397,708
Total assets	15,304,053				13,305,147				15,304,053	13,305,147
Americas [Member] | Private capital [Member]
Segment Reporting Information [Line Items]
Total revenues									69,422	76,872	66,653
Consolidated net earnings (loss)									31,637	42,644	40,354
Total assets	24,373				43,394				24,373	43,394
Europe [Member] | Real estate operations [Member]
Segment Reporting Information [Line Items]
Total revenues									436,206	309,575	78,545
Consolidated net earnings (loss)									326,126	223,950	43,452
Total assets	5,738,257				6,823,814				5,738,257	6,823,814
Europe [Member] | Private capital [Member]
Segment Reporting Information [Line Items]
Total revenues									37,047	46,087	54,835
Consolidated net earnings (loss)									21,699	30,708	41,200
Total assets	61,266				61,946				61,266	61,946
Asia [Member] | Real estate operations [Member]
Segment Reporting Information [Line Items]
Total revenues									231,514	161,288	82,692
Consolidated net earnings (loss)									179,682	123,087	60,912
Total assets	3,476,996				3,502,033				3,476,996	3,502,033
Asia [Member] | Private capital [Member]
Segment Reporting Information [Line Items]
Total revenues									20,310	14,660	1,038
Consolidated net earnings (loss)									9,623	9,305	313
Total assets	$ 6,108				$ 9,368				$ 6,108	$ 9,368