The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 159

-Paragraph 18

-Subparagraph f

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 323

-SubTopic 10

-Section 50

-Paragraph 3

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=6382943&loc=d3e33918-111571

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher AICPA

-Name Accounting Principles Board Opinion (APB)

-Number 18

-Paragraph 20

-Subparagraph a (1)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
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Equity Investments in Real Estate (Details 1) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2012 C 1000 BV [Member]	Dec. 31, 2011 C 1000 BV [Member]	Jan. 31, 2011 C 1000 BV [Member]	Dec. 31, 2012 Uhaul Moving Partners Inc And Mercury Partners Lp [Member]	Dec. 31, 2011 Uhaul Moving Partners Inc And Mercury Partners Lp [Member]	May 31, 2011 Uhaul Moving Partners Inc And Mercury Partners Lp [Member]	Dec. 31, 2012 Berry Plastics Corporation [Member]	Dec. 31, 2011 Berry Plastics Corporation [Member]	Dec. 31, 2012 Tesco Plc [Member]	Dec. 31, 2011 Tesco Plc [Member]	Dec. 31, 2012 Hellweg Die Profi Baumarkt Gmbh And Co KG [Member]	Dec. 31, 2011 Hellweg Die Profi Baumarkt Gmbh And Co KG [Member]	May 31, 2011 Hellweg Die Profi Baumarkt Gmbh And Co KG [Member]	Dec. 31, 2012 Eroski Sociedad Cooperativa Mallorca [Member]	Dec. 31, 2011 Eroski Sociedad Cooperativa Mallorca [Member]	Dec. 31, 2012 Dicks Sporting Goods Inc [Member]	Dec. 31, 2011 Dicks Sporting Goods Inc [Member]	May 31, 2011 Dicks Sporting Goods Inc [Member]	Dec. 31, 2012 BPS Partners, LLC	Oct. 31, 2012 BPS Partners, LLC	Dec. 31, 2011 BPS Partners, LLC	Dec. 31, 2012 Shelborne	Dec. 31, 2012 I-Drive Live
Ownership interest in equity investments:
Ownership interest, percentage			85.00%		85.00%	12.00%		12.00%	50.00%		49.00%		33.00%		33.00%	30.00%		45.00%		45.00%	15.00%	15.00%
Equity investments in real estate	$ 275,133	$ 187,067	$ 81,516	$ 89,063		$ 28,019	$ 28,956		$ 18,529	$ 19,411	$ 17,487	$ 17,923	$ 22,827	$ 16,817		$ 9,336	$ 9,158	$ 5,010	$ 5,739		$ 26,253		$ 0	$ 63,896	$ 2,260