Non-Controlling Interests, Preferred Shares, Common Shares and Common Shares in Treasury (Tables)

12 Months Ended

Dec. 31, 2011

Non-Controlling Interests, Preferred Shares, Common Shares and Common Shares in Treasury [Abstract]

Non-controlling interests

	December 31,
	2011		2010
Consolidated joint venture interests primarily outside the United States	$	21.6	$	27.3
Shopping centers and development parcels in various states		3.2		3.4
Operating partnership units		7.4		7.4
	$	32.2	$	38.1

Preferred shares outstanding

	December 31,
	2011		2010
Class G — 8.0% cumulative redeemable preferred shares, without par value, $250 liquidation value; 750,000 shares authorized; 720,000 shares issued and outstanding at December 31, 2010	$	—	$	180,000
Class H — 7.375% cumulative redeemable preferred shares, without par value, $500 liquidation value; 750,000 shares authorized; 410,000 shares issued and outstanding at December 31, 2011 and 2010		205,000		205,000
Class I — 7.5% cumulative redeemable preferred shares, without par value, $500 liquidation value; 750,000 shares authorized; 340,000 shares issued and outstanding at December 31, 2011 and 2010		170,000		170,000
	$	375,000	$	555,000

Common shares through open market sales

	Number of Shares Sold		Average Price Per Share		Net Proceeds
2011		9.5	$	13.71	$	129.7
2010		53.0	$	8.33	$	441.3
2009		23.5	$	8.78	$	204.5

Fair value of the equity derivative instruments

	Liability Derivatives
	December 31, 2011			December 31, 2010
Derivatives Not Designated as Hedging Instruments	Balance Sheet Location	Fair Value		Balance Sheet Location	Fair Value
Warrants	Equity derivative liability	$	—	Equity derivative liability	$	96.2

Company's warrants on net income (loss)

Derivatives Not Designated as Hedging Instruments		Year Ended December 31,
	Income Statement Location	2011		2010			2009
Warrants	Gain (loss) on equity derivative instruments	$	21.9	$	(40.1	)	$	(46.9	)
Equity forward — issued shares	Gain (loss) on equity derivative instruments		—		—			(152.9	)
		$	21.9	$	(40.1	)	$	(199.8	)

Fair value hierarchy of the valuation techniques used by the Company

	Fair Value Measurements
	Level 1		Level 2		Level 3		Total
December 31, 2010
Warrants	$	—	$	—	$	96.2	$	96.2
December 31, 2009
Warrants	$	—	$	—	$	56.1	$	56.1

Reconciliation of the beginning and ending balances of equity derivative instruments

	Equity Derivative Instruments— Liability
Balance of Level 3 at January 1, 2009	$	—
Initial valuation		9.2
Unrealized loss		46.9
Balance of Level 3 at December 31, 2009	$	56.1
Unrealized loss		40.1
Balance of Level 3 at December 31, 2010	$	96.2
Unrealized gain		(21.9	)
Transfer out of liability to paid-in capital		(74.3	)
Balance of Level 3 at December 31, 2011	$	—