This item represents disclosure of the amount of dividends or other distributions received from unconsolidated subsidiaries, certain corporate joint ventures, and certain noncontrolled corporation; these investments are accounted for under the equity method of accounting. This element excludes distributions that constitute a return of investment, which are classified as investing activities.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 95
-Paragraph 28

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 03
-Paragraph 13
-Article 5

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Principles Board Opinion (APB)
-Number 18
-Paragraph 19

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This item represents an other than temporary decline in value that has been recognized against an investment accounted for under the equity method of accounting. The excess of the carrying amount over the fair value of the investment represents the amount of the write down which is or was reflected in earnings. The written down value is a new cost basis with the adjusted value of the investment becoming its new carrying value subject to the equity accounting method. Evidence of a loss in value might include, but would not necessarily be limited to, absence of an ability to recover the carrying amount of the investment or inability of the investee to sustain an earnings capacity which would justify the carrying amount of the investment.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Principles Board Opinion (APB)
-Number 18
-Paragraph 19
-Subparagraph h

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

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 159
-Paragraph 18
-Subparagraph f

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Principles Board Opinion (APB)
-Number 18
-Paragraph 20
-Subparagraph a (1)

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This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment losses recognized.

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The cash outflow associated with the investment in or advances to an entity in which the reporting entity shares control of the entity with another party or group.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 95
-Paragraph 17
-Subparagraph b

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The contract termination fee recognized as a result of the merger.

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The amount of charge against earnings resulting from the aggregate write down of assets from their carrying value to their fair value reported by an equity method investment of the entity.

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Other merger expenses incurred by the REIT.

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Net gains recognized by the REIT as a result of asset sales arising from the merger.

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The net loss recognized by the REIT as a result of the prepayment of certain nonrecourse mortgages.

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Equity Investment in Real Estate and the REITs (Details) (USD $)	3 Months Ended		6 Months Ended									3 Months Ended		6 Months Ended					3 Months Ended		6 Months Ended			3 Months Ended		6 Months Ended															1 Months Ended					6 Months Ended				12 Months Ended				12 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010	Dec. 31, 2010	Jun. 30, 2011 CPA 14 [Member] REITs [Member]	Dec. 31, 2010 CPA 14 [Member] REITs [Member]	Jun. 30, 2011 CPA 15 [Member] REITs [Member]	Dec. 31, 2010 CPA 15 [Member] REITs [Member]	Jun. 30, 2011 CPA 16 [Member] REITs [Member]	Dec. 31, 2010 CPA 16 [Member] REITs [Member]	Jun. 30, 2011 CPA 17 [Member] REITs [Member]	Jun. 30, 2010 CPA 17 [Member] REITs [Member]	Jun. 30, 2011 CPA 17 [Member] REITs [Member]	Jun. 30, 2010 CPA 17 [Member] REITs [Member]	Dec. 31, 2010 CPA 17 [Member] REITs [Member]	Jun. 30, 2011 CWI [Member] REITs [Member]	Dec. 31, 2010 CWI [Member] REITs [Member]	Jun. 30, 2011 REITs [Member]	Jun. 30, 2010 REITs [Member]	Jun. 30, 2011 REITs [Member]	Jun. 30, 2010 REITs [Member]	Dec. 31, 2010 REITs [Member]	Jun. 30, 2011 Real Estate [Member]	Jun. 30, 2010 Real Estate [Member]	Jun. 30, 2011 Real Estate [Member]	Jun. 30, 2010 Real Estate [Member]	Dec. 31, 2010 Real Estate [Member]	Jun. 30, 2011 Real Estate [Member] SchulerAG [Member]	Dec. 31, 2010 Real Estate [Member] SchulerAG [Member]	Jun. 30, 2011 Real Estate [Member] Carrefour France SAS [Member]	Dec. 31, 2010 Real Estate [Member] Carrefour France SAS [Member]	Jun. 30, 2011 Real Estate [Member] New York Times Company [Member]	Dec. 31, 2010 Real Estate [Member] New York Times Company [Member]	Jun. 30, 2011 Real Estate [Member] US Airways Group Inc [Member]	Dec. 31, 2010 Real Estate [Member] US Airways Group Inc [Member]	Jun. 30, 2011 Real Estate [Member] Medica France SA [Member]	Dec. 31, 2010 Real Estate [Member] Medica France SA [Member]	Jun. 30, 2011 Real Estate [Member] HologicInc [Member]	Dec. 31, 2010 Real Estate [Member] HologicInc [Member]	Jan. 31, 2011 Real Estate [Member] Childtime Childcare Inc [Member]	Jun. 30, 2011 Real Estate [Member] Childtime Childcare Inc [Member]	Dec. 31, 2010 Real Estate [Member] Childtime Childcare Inc [Member]	Jun. 30, 2011 Real Estate [Member] Consolidated Systems Inc [Member]	Dec. 31, 2010 Real Estate [Member] Consolidated Systems Inc [Member]	Jun. 30, 2011 Real Estate [Member] Symphony IRI Group Inc [Member]	Dec. 31, 2010 Real Estate [Member] Symphony IRI Group Inc [Member]	Jun. 30, 2011 Real Estate [Member] Hellweg Die Profi Baumarkte GmbH Co Kg [Member]	Dec. 31, 2010 Real Estate [Member] Hellweg Die Profi Baumarkte GmbH Co Kg [Member]	Dec. 31, 2010 Real Estate [Member] Federal Express Corporation [Member]	Jun. 30, 2011 Real Estate [Member] Federal Express Corporation [Member]	Jun. 30, 2011 Real Estate [Member] Amylin Pharmaceuticals Inc [Member]	Dec. 31, 2010 Real Estate [Member] Amylin Pharmaceuticals Inc [Member]	Dec. 31, 2007 Amylin Pharmaceuticals Inc [Member]
Schedule Of Equity Method Investments [Line Items]
Equity Method Investment, Ownership Percentage						0.00%	9.20%	7.40%	7.10%	17.50%	5.60%	0.80%		0.80%		0.60%	0.80%	100.00%											33.00%		46.00%		18.00%		75.00%		46.00%		36.00%			34.00%		60.00%		33.00%		5.00%			100.00%	100.00%
Equity investments in real estate and the REITs	$ 528,012,000		$ 528,012,000		$ 322,294,000	$ 0	$ 87,209,000	$ 90,004,000	$ 87,008,000	$ 332,463,000	$ 62,682,000	$ 14,401,000		$ 14,401,000		$ 8,156,000	$ 129,000	$ 0	$ 436,997,000		$ 436,997,000		$ 245,055,000	$ 91,015,000		$ 91,015,000		$ 77,239,000	$ 23,246,000	$ 20,493,000	$ 20,856,000	$ 18,274,000	$ 19,275,000	$ 20,191,000	$ 7,738,000	$ 7,934,000	$ 5,085,000	$ 5,232,000	$ 4,728,000	$ 4,383,000		$ 4,140,000	$ 1,862,000	$ 3,400,000	$ 3,388,000	$ 1,437,000	$ 3,375,000	$ 1,110,000	$ 1,086,000	$ (4,272,000)	$ 0	$ 0	$ (4,707,000)
Contribution to the venture																																									2,100,000
Impairment charges																			(29,831,000)	(886,000)	(39,839,000)	(12,980,000)		(40,000)	0	(8,602,000)	0																			8,600,000
Equity Method Investment Other Than Temporary Impairment																																														200,000
Distributions received from equity investment	1,973,000	1,187,000	3,788,000	1,693,000								2,000,000	1,200,000	3,800,000	1,700,000																																			5,500,000				17,600,000
Net Gains Recognized As Result of Asset Sales						78,800,000													7,400,000		7,400,000
Net Gain Of Reit Fair Value										13,700,000									2,400,000		2,400,000
Contract Termination Fee										34,300,000									4,900,000		4,900,000
Merger Expenses Incurred By Reit										8,500,000									1,500,000		1,500,000
Net Loss Resulting From Prepayment Of Nonrecourse Mortgages										$ 2,800,000									$ 500,000		$ 500,000