Summary of Significant Accounting Policies - Real Estate Properties (Details) (USD $)	12 Months Ended
	Dec. 31, 2013 Property	Dec. 31, 2012	Dec. 31, 2011 Property
Balances of major classes of depreciable assets and their respective estimated useful lives [Abstract]
Estimated useful life of depreciable assets	40 years
Total depreciable assets	$ 2,548,036,000	$ 1,762,566,000
Depreciation expense	72,300,000	50,700,000	76,500,000
Number of real estate properties	43		2
Impairment loss on real estate, including continuing and discontinued operations	10,200,000	9,200,000	196,300,000
Impairment loss on real estate	0	5,700,000	6,420,000
Impairment loss on real estate - discontinued operations	10,200,000	3,500,000	189,940,000
Finite-Lived Intangible Assets [Line Items]
Amortization of above (below) market leases	2,210,000	5,015,000	2,695,000
Total	166,756,000	118,097,000
Above and Below Market Leases
Finite-Lived Intangible Assets [Line Items]
Amortization of above (below) market leases	2,200,000	5,000,000	2,700,000
2014	11,613,000
2015	7,385,000
2016	6,997,000
2017	6,121,000
2018	3,661,000
Thereafter	11,134,000
Total	46,911,000
Lease In Place Value
Finite-Lived Intangible Assets [Line Items]
Amortization of above (below) market leases	26,900,000	15,000,000	11,100,000
2014	45,520,000
2015	26,386,000
2016	21,260,000
2017	15,175,000
2018	9,108,000
Thereafter	19,128,000
Total	136,577,000
Land [Member]
Balances of major classes of depreciable assets and their respective estimated useful lives [Abstract]
Total depreciable assets	278,780,000	159,039,000
Buildings and garages [Member]
Balances of major classes of depreciable assets and their respective estimated useful lives [Abstract]
Estimated useful life of depreciable assets	40 years 0 months 0 days
Total depreciable assets	1,973,668,000	1,369,493,000
Building improvements [Member]
Balances of major classes of depreciable assets and their respective estimated useful lives [Abstract]
Total depreciable assets	78,450,000	65,328,000
Building improvements [Member] | Maximum [Member]
Balances of major classes of depreciable assets and their respective estimated useful lives [Abstract]
Estimated useful life of depreciable assets	40 years 0 months 0 days
Building improvements [Member] | Minimum [Member]
Balances of major classes of depreciable assets and their respective estimated useful lives [Abstract]
Estimated useful life of depreciable assets	7 years 0 months 0 days
Tenant improvements [Member]
Balances of major classes of depreciable assets and their respective estimated useful lives [Abstract]
Total depreciable assets	$ 217,138,000	$ 168,706,000
LOUISIANA | Assets Held-for-sale [Member]
Balances of major classes of depreciable assets and their respective estimated useful lives [Abstract]
Area of land	12
Condominium Project | Murano [Member]
Balances of major classes of depreciable assets and their respective estimated useful lives [Abstract]
Ownership percentage of noncontrolling interest	27.00%
Ownership percentage	73.00%
Property Distributions prior to Established Return Thresholds, Percent	73.00%