Gain on Sales of Real Estate (Details) (USD $)	3 Months Ended
Mar. 31, 2015 item	Mar. 31, 2014 item
Sales of investment properties
Sales proceeds		$ 6,918,000
New properties and properties under development
Sales of investment properties
Number of properties sold	9	11
Sales proceeds	22,300,000	12,700,000
Gain on sales of investment properties	7,200,000	3,900,000
New properties and properties under development \| Discontinued Operations
Sales of investment properties
Gain on sales of investment properties		2,600,000
New properties and properties under development \| Crest Net Lease, Inc. (Crest)
Sales of investment properties
Number of properties sold		1
Sales proceeds		$ 820,000

Number of sales of real estate properties held for investment, that is, it is part of an investing activity during the period.

No definition available.

+ Details

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Balance Type:	na
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- Definition

The difference between the carrying value and the sale price of real estate or properties that were intended to be sold or held for capital appreciation or rental income. This element refers to the gain (loss) included in earnings and not to the cash proceeds of the sale. This element is a noncash adjustment to net income when calculating net cash generated by operating activities using the indirect method.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

+ Details

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Namespace Prefix:	us-gaap_
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Period Type:	duration

- Definition

The cash inflow associated with the sale of other real estate not otherwise defined in the taxonomy.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 12

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3179-108585

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Investing Activities

-URI http://asc.fasb.org/extlink&oid=6516133

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- Details

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- Details

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