Business Segments - Segment Reporting, Reconciliation of Revenues, Operating Income and Assets (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013	Dec. 31, 2013	Dec. 31, 2012
Segment Reporting Information [Line Items]
Total revenues	$ 434,682	$ 479,971
General and administrative expenses	(63,203)	(56,197)
Depreciation and amortization	(160,280)	(172,119)
Earnings from unconsolidated entities, net	29,746	24,768
Interest expense	(85,523)	(114,641)
Interest and other income, net	14,050	11,627
Gains on acquisitions and dispositions of investments in real estate, net	17,055	338,845
Foreign currency and derivative gains (losses), net	(28,184)	884
Gains (losses) on early extinguishment of debt, net	273	(17,351)
Consolidated net earnings (loss)	12,003	296,932
Earnings before income taxes	18,883	341,171
Investments in and advances to unconsolidated entities	4,687,922		4,430,239
Cash and cash equivalents	188,886	785,359	491,129	100,810
Total assets	24,655,148		24,572,307
Operating Segments [Member]
Segment Reporting Information [Line Items]
Total revenues	434,682	479,971
Consolidated net earnings (loss)	294,949	325,355
Total assets	19,306,003		19,190,865
Operating Segments [Member] | Real Estate Operations [Member]
Segment Reporting Information [Line Items]
Total revenues	389,372	446,336
Consolidated net earnings (loss)	273,802	311,629
Total assets	19,220,876		19,104,750
Operating Segments [Member] | Investment Management [Member]
Segment Reporting Information [Line Items]
Total revenues	45,310	33,635
Consolidated net earnings (loss)	21,147	13,726
Total assets	85,127		86,115
Operating Segments [Member] | Americas [Member] | Real Estate Operations [Member]
Segment Reporting Information [Line Items]
Total revenues	356,125	308,400
Consolidated net earnings (loss)	253,461	216,128
Total assets	16,276,368		16,293,109
Operating Segments [Member] | Americas [Member] | Investment Management [Member]
Segment Reporting Information [Line Items]
Total revenues	14,575	16,187
Consolidated net earnings (loss)	2,056	2,883
Total assets	21,836		22,154
Operating Segments [Member] | Europe [Member] | Real Estate Operations [Member]
Segment Reporting Information [Line Items]
Total revenues	16,188	99,467
Consolidated net earnings (loss)	8,224	67,206
Total assets	1,675,895		1,634,867
Operating Segments [Member] | Europe [Member] | Investment Management [Member]
Segment Reporting Information [Line Items]
Total revenues	21,700	10,613
Consolidated net earnings (loss)	13,684	6,871
Total assets	59,816		60,327
Operating Segments [Member] | Asia [Member] | Real Estate Operations [Member]
Segment Reporting Information [Line Items]
Total revenues	17,059	38,469
Consolidated net earnings (loss)	12,117	28,295
Total assets	1,268,613		1,176,774
Operating Segments [Member] | Asia [Member] | Investment Management [Member]
Segment Reporting Information [Line Items]
Total revenues	9,035	6,835
Consolidated net earnings (loss)	5,407	3,972
Total assets	3,475		3,634
Reconciling Items [Member]
Segment Reporting Information [Line Items]
General and administrative expenses	(63,203)	(56,197)
Depreciation and amortization	(160,280)	(172,119)
Earnings from unconsolidated entities, net	29,746	24,768
Interest expense	(85,523)	(114,641)
Interest and other income, net	14,050	11,627
Gains on acquisitions and dispositions of investments in real estate, net	17,055	338,845
Foreign currency and derivative gains (losses), net	(28,184)	884
Gains (losses) on early extinguishment of debt, net	273	(17,351)
Consolidated net earnings (loss)	(276,066)	15,816
Investments in and advances to unconsolidated entities	4,687,922		4,430,239
Notes receivable backed by real estate and other	191,703		192,042
Cash and cash equivalents	188,886		491,129
Other assets	280,634		268,032
Total assets	$ 5,349,145		$ 5,381,442