Intangibles (Details) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Intangible assets:
Accumulated amortization	$ (458,919,000)	$ (352,692,000)
Net intangible assets	1,040,609,000	1,152,842,000
Remaining weighted average amortization period of lease-related intangible assets (in years)	19 years 9 months 18 days	19 years 3 months 18 days
Intangible liabilities:
Accumulated amortization	(119,549,000)	(78,560,000)
Purchase option intangibles	29,294,000	36,048,000
Net intangible liabilities	371,047,000	416,361,000
Remaining weighted average amortization period of lease-related intangible liabilities (in years)	15 years 1 month 6 days	15 years 3 months 18 days
Intangibles
Net amortization expense	65,200,000	123,300,000	62,500,000
Estimated net amortization of the intangibles during 2014	57,800,000
Estimated net amortization of the intangibles during 2015	35,000,000
Estimated net amortization of the intangibles during 2016	24,000,000
Estimated net amortization of the intangibles during 2017	14,400,000
Estimated net amortization of the intangibles during 2018	8,900,000
Above market lease intangibles
Intangible assets:
Intangible assets, gross	214,353,000	215,367,000
Remaining weighted average amortization period of lease-related intangible assets (in years)	8 years 4 months 24 days	9 years 6 months
In-place and other lease intangibles
Intangible assets:
Intangible assets, gross	795,829,000	766,337,000
Remaining weighted average amortization period of lease-related intangible assets (in years)	24 years 1 month 6 days	23 years 3 months 18 days
Goodwill and other intangibles
Intangible assets:
Intangible assets, gross	489,346,000	523,830,000
Remaining weighted average amortization period of lease-related intangible assets (in years)	8 years 7 months 6 days	8 years 7 months 6 days
Below market lease intangibles
Intangible liabilities:
Intangible liabilities, gross	429,199,000	429,907,000
Remaining weighted average amortization period of lease-related intangible liabilities (in years)	14 years 8 months 12 days	15 years 3 months 18 days
Other lease intangibles
Intangible liabilities:
Intangible liabilities, gross	$ 32,103,000	$ 28,966,000
Remaining weighted average amortization period of lease-related intangible liabilities (in years)	24 years 9 months 18 days	15 years 9 months 18 days