Real Estate Investments (Details) (USD $)	Dec. 31, 2014 sqft	Dec. 31, 2013 sqft
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Number of Real Estate Properties	209us-gaap_NumberOfRealEstateProperties	130us-gaap_NumberOfRealEstateProperties
Gross Leasable Area	4,315,000us-gaap_LandSubjectToGroundLeases	3,662,000us-gaap_LandSubjectToGroundLeases
Land	$ 195,091,303us-gaap_Land	$ 162,096,646us-gaap_Land
Buildings	393,826,467	297,464,585
Property under Development	229,242us-gaap_DevelopmentInProcess	6,959,174us-gaap_DevelopmentInProcess
Property Held for Sale	0us-gaap_RealEstateHeldforsale	4,845,504us-gaap_RealEstateHeldforsale
Gross Real Estate Investments	589,147,012	471,365,909
Less accumulated depreciation	(59,089,851)	(60,633,824)
Net Real Estate Investments	$ 530,057,161us-gaap_RealEstateInvestmentPropertyNet	$ 410,732,085us-gaap_RealEstateInvestmentPropertyNet

The current amount of expenditures for a real estate project that has not yet been completed.

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- Details

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- Definition

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

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount before accumulated depletion of real estate held for productive use, excluding land held for sale.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section 45

-Paragraph 4

-Subparagraph (e)

-URI http://asc.fasb.org/extlink&oid=28358313&loc=d3e6812-107765

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.13)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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- Definition

Area of land subject to a ground lease.

+ References

No definition available.

+ Details

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Data Type:	num:areaItemType
Balance Type:	na
Period Type:	instant

- Definition

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

+ References

No definition available.

+ Details

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- Definition

Carrying amount as of the balance sheet date of investments in land and buildings held for sale, excluding real estate considered to be inventory of the entity.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

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

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.1(3))

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 1

-Article 7

+ Details

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- Definition

Amount of real estate investment property which may include the following: (1) land available-for-sale; (2) land available-for-development; (3) investments in building and building improvements; (4) tenant allowances; (5) developments in-process; (6) rental properties; and (7) other real estate investments.

+ References

+ Details

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- Definition

Amount of real estate investment property, net of accumulated depreciation, which may include the following: (1) land available-for-sale; (2) land available-for-development; (3) investments in building and building improvements; (4) tenant allowances; (5) developments in-process; (6) rental properties; and (7) other real estate investments.

+ References

+ Details

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