Mall Sales - Additional Information (Detail) (USD $)	1 Months Ended		12 Months Ended			0 Months Ended	1 Months Ended
	May 31, 2004	Apr. 30, 2004	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Jun. 24, 2011	Feb. 29, 2008
Sale of Mall Assets [Line Items]
Mall sale, deferred proceeds			$ 268,710,000	$ 268,541,000
The Grand Canal Shoppes [Member]
Sale of Mall Assets [Line Items]
Mall sale, proceeds		766,000,000
Mall sale, realized gain	417,600,000
Operating leases, term of contract		89 years
Mall sale, deferred rent	109,200,000
Amortization of deferred rent, recognized			1,200,000	1,200,000	1,200,000
Net present value of the lease payments	77,200,000
Amortization of deferred gain, recognized			3,100,000	3,500,000	3,500,000
The Grand Canal Shoppes [Member] | Theater Space [Member]
Sale of Mall Assets [Line Items]
Sales leaseback, term of lease		25 years
Sales leaseback, annual rental payments		3,300,000
The Grand Canal Shoppes [Member] | Gondola Ride [Member]
Sale of Mall Assets [Line Items]
Sales leaseback, term of lease		25 years
Sales leaseback, annual rental payments		3,500,000
The Grand Canal Shoppes [Member] | Office Space [Member]
Sale of Mall Assets [Line Items]
Sales leaseback, term of lease		10 years
Sales leaseback, term of lease, extension option		65 years
Sales leaseback, annual rental payments		900,000
The Shoppes At The Palazzo [Member]
Sale of Mall Assets [Line Items]
Mall sale, proceeds						295,400,000
Operating leases, term of contract							89 years
Mall sale, deferred rent							22,500,000
Sales leaseback, term of lease		10 years
Sales leaseback, term of lease, extension option		10 years
Sales leaseback, annual rental payments		700,000
Minimum lease payments, 2015			900,000
Minimum lease payments, 2016			900,000
Minimum lease payments, 2017			900,000
Minimum lease payments, 2018			500,000
Mall sale, deferred proceeds			$ 268,710,000			$ 266,200,000