Note 5 - Other Real Estate Investments (Details) (USD $) Share data in Millions, unless otherwise specified	3 Months Ended			6 Months Ended
	Jun. 30, 2013		Jun. 30, 2012	Jun. 30, 2013		Jun. 30, 2012	Dec. 31, 2012
Note 5 - Other Real Estate Investments (Details) [Line Items]
Equity Method Investments (in Dollars)	$ 1,392,418,000			$ 1,392,418,000			$ 1,428,155,000
Number of Real Estate Properties	4			4
Income (Loss) from Equity Method Investments (in Dollars)	59,500,000		30,400,000	83,616,000		65,090,000
Business Combination, Step Acquisition, Equity Interest in Acquiree, Remeasurement Gain (in Dollars)	(1,459,000)		12,147,000	21,711,000		14,156,000
Cost Method Investments (in Dollars)	6,976,000			6,976,000
Marketable Securities (in Dollars)	71,009,000	[1]		71,009,000	[1]		36,541,000	[1]
Albertsons [Member] | Supervalu Transaction [Member]
Note 5 - Other Real Estate Investments (Details) [Line Items]
Number of Real Estate Properties	414			414
Payments to Acquire Equity Method Investments (in Dollars)				22,300,000
Sale of Stock, Percentage of Ownership after Transaction				15.20%
NAI Group Holdings [Member] | Supervalu Transaction [Member]
Note 5 - Other Real Estate Investments (Details) [Line Items]
Number of Real Estate Properties	456			456
Cost Method Investments (in Dollars)	14,900,000			14,900,000
Cost Method Investment, Ownership Percentage	15.00%			15.00%
Number of Grocery Banners	4			4
Supervalu Transaction [Member]
Note 5 - Other Real Estate Investments (Details) [Line Items]
Investment Owned, at Cost (in Dollars)	70,800,000			70,800,000
Supervalu [Member]
Note 5 - Other Real Estate Investments (Details) [Line Items]
Investment Owned, Balance, Shares (in Shares)	8.2			8.2
Supervalu Transaction [Member]
Note 5 - Other Real Estate Investments (Details) [Line Items]
Marketable Securities (in Dollars)	33,600,000			33,600,000
Net Leased Properties [Member] | Preferred Equity Capital [Member]
Note 5 - Other Real Estate Investments (Details) [Line Items]
Number of Real Estate Properties	392			392
Preferred Equity Capital [Member]
Note 5 - Other Real Estate Investments (Details) [Line Items]
Equity Method Investments (in Dollars)	263,200,000			263,200,000
Number of Real Estate Properties	492			492
Income (Loss) from Equity Method Investments (in Dollars)				17,300,000		16,600,000
Equity Method Investment, Realized Gain (Loss) on Disposal (in Dollars)				4,400,000		4,500,000
Number of Capital Transactions	1		8	1		8
Number of Agreements			1			1
Business Combination, Step Acquisition, Equity Interest in Acquiree, Remeasurement Gain (in Dollars)				$ 9,600,000

[1] As of June 30, 2013 and December 31, 2012, the Company determined that $68.0 million and $33.4 million, respectively, of the marketable securities estimated fair value were classified within Level 1 of the fair value hierarchy and the remaining $3.3 million and $3.4 million, respectively, were classified within Level 3 of the fair value hierarchy.