Net Investments in Properties (Details) (USD $)	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010	Dec. 31, 2010
Other Investments [Abstract]
Amortization Period			one year to 40 years
Amortization Of Intangible Assets	$ 1,700,000	$ 1,300,000	$ 2,200,000	$ 3,100,000
Net lease intangibles recorded	81,800,000		81,800,000
Fair value of properties acquired			174,800,000
Fair Value of Nonrecourse Debt Of All Properties Acquired	117,100,000		117,100,000
Balance Sheet Impact Of Acquisition Of Properties			40,800,000
Gain On Change In Control Of Interests	27,859,000	0	27,859,000	0
Balance Sheet Impact Of Consolidating Properties Real Estate			90,200,000
Schedule Of Investments [Line Items]
Real Estate Investment Property, Accumulated Depreciation	129,072,000		129,072,000		122,312,000
Real Estate Investment Property, Net	627,599,000		627,599,000		548,131,000
Real Estate Business [Member]
Schedule Of Investments [Line Items]
Land	114,800,000		114,800,000		111,660,000
Investment Building And Building Improvements	532,123,000		532,123,000		448,932,000
Real Estate Investment Property, Accumulated Depreciation	113,380,000		113,380,000		108,032,000
Real Estate Investment Property, Net	533,543,000		533,543,000		452,560,000
Operating Real Estate Business [Member]
Schedule Of Investments [Line Items]
Land	24,030,000		24,030,000		24,030,000
Investment Building And Building Improvements	85,718,000		85,718,000		85,821,000
Real Estate Investment Property, Accumulated Depreciation	15,692,000		15,692,000		14,280,000
Real Estate Investment Property, Net	$ 94,056,000		$ 94,056,000		$ 95,571,000

The aggregate amount assigned to a major class of finite-lived intangible assets acquired either individually or as part of a group of assets (in either an asset acquisition or business combination). A major class is composed of intangible assets that can be grouped together because they are similar, either by their nature or by their use in the operations of a company.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 142
-Paragraph 44
-Subparagraph a(1)

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The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by (used in) operations using the indirect method.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 142
-Paragraph 45
-Subparagraph a(2)

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The fair value of assets acquired in noncash investing or financing activities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 95
-Paragraph 32

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Aggregate of the carrying amounts as of the balance sheet date of investments in building and building improvements.

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- Definition

Carrying amount as of the balance sheet date of real estate held for productive use. This excludes land held for sale.

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The cumulative amount of depreciation for real estate property held for investment purposes.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 03
-Paragraph 1
-Article 7

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The net book value of real estate property held for investment purposes.

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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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Period over Amortization for Intangibles

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The impact to the balance sheet as a result of consolidating the wholly-owned properties acquired.

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Represents the impact to the Real Estate recorded on the balance sheet after the consolidation of certain properties.

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Amount of fair value of all of the nonrecourse debt acquired when purchasing the remaining interests in certain properties.

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The gain recorded in the period arising from the change in ownership of an equity investment.

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