Real Estate Investments Real Estate Investments (Details) (USD $)	6 Months Ended	12 Months Ended
Jun. 30, 2011	Dec. 31, 2010
Unconsolidated Properties [Member] \| Macquarie Countrywide Regency DESCO LLC [Member]
Business Acquisition [Line Items]
Equity Method Investment, Ownership Percentage	16.35%
Equity Method Investment Sold, Carrying Amount	$ 18,800,000
Disposition Fee, Income Received from Sale of Real Estate	5,000,000
Consulting Fee, Income from Sale of Real Estate	1,000,000
Consulting Fee, Income Recognized for Sale of Real Estate	250,000
Number of Real Estate Properties		32
Equity Method Investment, Summarized Financial Information, Assets		366,800,000
Equity Method Investment, Summarized Financial Information, Net Income (Loss)		4,900,000
Equity Method Investment, Underlying Equity in Net Assets		60,000,000
Income (Loss) from Equity Method Investments		817,000
Unconsolidated Properties [Member]
Business Acquisition [Line Items]
Number of Real Estate Properties	147
Wholly Owned Properties [Member]
Business Acquisition [Line Items]
Business Acquisition, Purchase Price Allocation, Current Assets, Description	11,000,000
Mortgage loans assumed for aquistion of real estate	5,900,000
Debt Instrument, Unamortized Premium	310,000
Acquired Finite-lived Intangible Asset, Amount	1,700,000
Acquired Finite Lived Intangible Liability Amount	$ 2,600,000
Limited Liability Company (LLC) or Limited Partnership (LP), Managing Member or General Partner, Ownership Interest	100.00%
Number of Real Estate Properties	220

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The total cost of the acquired entity including the cash paid to shareholders of acquired entities, fair value of debt and equity securities issued to shareholders of acquired entities, the fair value of the liabilities assumed, and direct costs of the acquisition.

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The amount of debt premium that was originally recognized at the issuance of the instrument that has yet to be amortized.

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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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The amount of assets reported by an equity method investment of the entity.

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The amount of net income (loss) reported by an equity method investment of the entity.

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This item represents the entity's ownership percentage in the investee multiplied by the investee's total equity.

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The number of units or percentage investment held by the managing member or general partner of the LLC or LP.

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The amount of debt that an Entity assumes in acquiring a business or in consideration for an asset received in a noncash (or part noncash) acquisition. Noncash is defined as transactions during a period that affect recognized assets or liabilities but that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

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The number of real estate properties owned as of the balance sheet date.

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