FINANCIAL INSTRUMENTS - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	9 Months Ended
	Sep. 30, 2012 Derivative		Dec. 31, 2011
Derivative [Line Items]
Aggregate Notional Amount	$ 633.1		$ 284.1
Principal amount of Senior Notes	300.0
Payment to the counter party	4.7
Unrealized Loss of hedging instrument	10.3
Approximate Fair value of notes	244.2		90.6
Carrying amount of notes	244.1		91.0
Tax Increment Financing Bonds ("TIF Bonds")	5.2	[1]	6.4	[1]
Derivative financial instruments	19.0		8.8
Number of interest rate derivatives held	10
Interest rate cash flow hedge gain (loss) to be reclassified during next 12 months, net	(6.6)
Treasury locks [Member]
Derivative [Line Items]
Aggregate Notional Amount	200.0
Eight interest rate swaps entered into in the first nine months of 2012 [Member]
Derivative [Line Items]
Aggregate Notional Amount	450.0
Interest Rate Swaps One [Member]
Derivative [Line Items]
Aggregate Notional Amount	$ 100.0

[1] Principal and interest are payable solely from the incremental real estate taxes, if any, generated by the respective shopping center and development project pursuant to the terms of the financing agreement.