Investments In Unconsolidated Real Estate Entities (Schedule Of Operation For Apartment LLCs) (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Revenues
Rental	$ 77,081	$ 70,499	$ 152,736	$ 139,592
Other property revenues	4,873	4,698	9,272	8,920
Total revenues	82,160	75,424	162,436	148,955
Expenses
Property operating and maintenance	35,231	33,206	69,868	65,823
Interest	11,103	14,437	22,748	28,912
Total expenses	59,239	57,011	118,288	113,468
Net income available to the Company	21,079	9,746	42,879	12,771
Company's share of net income in Apartment LLCs	495	346	6,941	555
Apartment LLCs [Member]
Revenues
Rental	6,152	5,842	12,194	11,611
Other property revenues	501	483	937	909
Total revenues	6,653	6,325	13,131	12,520
Expenses
Property operating and maintenance	2,555	2,331	5,082	4,794
Depreciation and amortization	1,428	1,480	3,033	2,954
Interest	2,258	2,555	4,625	5,081
Total expenses	6,241	6,366	12,740	12,829
Net loss from continuing operations	412	(41)	391	(309)
Gain (loss) from discontinued operations		(42)	21,607	(99)
Net income available to the Company	412	(83)	21,998	(408)
Company's share of net income in Apartment LLCs	$ 495	$ 346	$ 6,941	$ 555