Summary of Significant Accounting Policies Text (Details) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Aug. 18, 2011	Aug. 23, 2006
Number Of Unconsolidated Projects	3
Partially Owned Unconsolidated Properties	4
Indirect Ownership Interest Percentage	1.00%
Value of furniture and fixtures minimum range	$ 3,000
Value of furniture and fixtures maximum range	13,000
Lease Intangibles, Average Term	6
Capitalized Costs Development and Renovation	16,500,000	14,300,000	11,600,000
Accumulated Amortization, Deferred Finance Costs	33,400,000	32,200,000
Partially Owned Consolidated Properties	19
Partially Owned Consolidated Units	3,752
Noncontrolling Interests - Partially Owned Properties	126,583,000	77,688,000
Noncontrolling Interests Settlement Value	51,200,000
Convertible Debt				482,500,000	650,000,000
Debt Instrument, Interest Rate, Stated Percentage					3.85%
Debt Instrument, Interest Rate, Effective Percentage					5.80%
Expense incurred, net	586,854,000	455,236,000	460,172,000
Debt Instrument, Convertible, Carrying Amount of Equity Component	44,300,000				44,300,000
Effect Of Change In Accounting Principle On Earnings Net Of Tax			5,000,000
Effect of change in accounting Principle On Earnings Per Share Net Of Tax			$ 0.02
Retained Earnings Decrease	27,000,000
Cumulative effect On Notes From Adoption Of Accounting Principle	17,300,000
Furniture and Fixtures [Member]
Property, Plant and Equipment, Estimated Useful Lives	5
Furniture and Fixtures Maximum [Member]
Property, Plant and Equipment, Estimated Useful Lives	10
Building [Member]
Property, Plant and Equipment, Estimated Useful Lives	30
Building Improvements [Member]
Property, Plant and Equipment, Estimated Useful Lives	8
Replacements Minimum [Member]
Property, Plant and Equipment, Estimated Useful Lives	5
Replacements Maximum [Member]
Property, Plant and Equipment, Estimated Useful Lives	10
Renovations and Improvements Minimum [Member]
Property, Plant and Equipment, Estimated Useful Lives	5
Renovations and Improvements Maximum [Member]
Property, Plant and Equipment, Estimated Useful Lives	15
Minimum [Member]
Retail/Commercial Leases Term	5
Maximum [Member]
Retail/Commercial Leases Term	10
Limited Life Partnership Properties [Member]
Partially Owned Limited Life Partnership Properties	6
Noncontrolling Interest Balance Limited Life Partnerships	(9,800,000)
Convertible Debt [Member]
Expense incurred, net			$ 11,800,000
Unconsolidated Development Projects Held for and or Under Development [Domain]
Number Of Unconsolidated Projects	1
Unconsolidated Operating [Domain]
Partially Owned Unconsolidated Properties	4