Significant Acquisitions (Details) (USD $) Share data in Thousands, except Per Share data, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Significant Acquisitions
Number of properties acquired			3
Rental area of properties acquired (in square feet)			676,000
Aggregate purchase price of properties acquired, excluding closing costs and adjustments			$ 166,000,000
Estimated fair value of assets acquired at the date of acquisition
Real estate assets	120,750,000		120,750,000
Value of acquired real estate leases	47,474,000		47,474,000
Acquired unfavorable leases	(2,441,000)		(2,441,000)
Total	165,783,000		165,783,000
Pro forma operating results for the company and acquisitions
Revenue	40,420,000	32,863,000	76,959,000	66,216,000
Income from continuing operations	7,938,000	4,585,000	12,635,000	8,775,000
Net income	$ 10,381,000	$ 5,738,000	$ 35,130,000	$ 11,084,000
Weighted average shares outstanding	81,437	79,681	81,437	79,681
Income from continuing operations per share (in dollars per share)	$ 0.10	$ 0.06	$ 0.15	$ 0.11
Net income per share (in dollars per share)	$ 0.13	$ 0.07	$ 0.43	$ 0.14
North Carolina
Significant Acquisitions
Number of properties acquired			1
Texas
Significant Acquisitions
Number of properties acquired			2

The amount of acquisition cost of a business combination allocated to real estate assets acquired.

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The amount of acquisition cost of a business combination allocated to real estate leases acquired.

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The amount of acquisition cost of a business combination allocated to unfavorable leases acquired.

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Represents the number of properties acquired by the entity during the period.

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Represents the aggregate purchase price excluding closing costs and adjustments of real estate properties acquired by the entity during the period.

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The amount of square footage related to an acquired real estate property.

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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 pro forma basic net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(2)-(3)
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 141
-Paragraph 54
-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 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 141
-Paragraph 55
-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 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
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-Paragraph 68
-Subparagraph r(2, 3)
-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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The pro forma income from continuing operations before changes in accounting and extraordinary items, net of tax effect per basic share of common stock for a period as if the business combination or combinations had been completed at the beginning of a period.

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The amount of acquisition cost of a business combination allocated to assets acquired.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 141
-Paragraph 37
-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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The pro forma income from continuing operations before changes in accounting and extraordinary items, net of tax effect, for the period as if the business combination or combinations had been completed at the beginning of a period.

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The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

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The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

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The weighted average number of shares (units) outstanding in the calculation of pro forma basic earnings per share (earnings per unit), which is commonly presented in initial public offerings based on the terms of the offering.

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