Note 4 - Real Estate Under Development (Details Textual) $ in Thousands	9 Months Ended
Sep. 30, 2018 USD ($)	Sep. 30, 2017 USD ($)	Dec. 31, 2017 USD ($)
Real Estate Investment Property, Net, Total	$ 9,043,480		$ 9,817,875
Payments to Acquire Real Estate, Total	5,407	$ 110,802
Real Estate Under Development, Capitalized Costs of Interest, Real Estate Taxes, Insurance, Legal Costs and Payroll	36,900		$ 27,700
Real Estate Inventory, Capitalized Interest Costs Incurred	10,700
Real Estate Development Projects, Real Estate Taxes and Insurance Capitalized	2,500
Real Estate Development Projects, Payroll Costs Capitalized	1,200
Grand Parkway Marketplace II [Member]
Real Estate Investment Property, Net, Total	47,400
Real Estate Investment, Capitazlized Costs	$ 5,200
Real Estate Under Development [Member]
Number of Real Estate Properties	3
Real Estate Properties, Future Development [Member]
Number of Real Estate Properties	2
Parcel Adjacent to Development Project [Member]
Payments to Acquire Real Estate, Total	$ 4,600

The amount of payroll costs associated with real estate development projects that has been capitalized.

No definition available.

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- Definition

The amount of real estate taxes and insurance from real estate development projects that has been capitalized.

+ References

No definition available.

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- Definition

The amount of capitalized costs associated with a real estate investment.

+ References

No definition available.

+ Details

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- Definition

Represents capitalized costs of interest, real estate taxes, insurance, legal costs and payroll related to real estate under development.

+ References

No definition available.

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- Definition

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

+ References

No definition available.

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- Definition

The cash outflow from the acquisition of a piece of land, anything permanently fixed to it, including buildings, structures on it and so forth; includes real estate intended to generate income for the owner; excludes real estate acquired for use by the owner.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3213-108585

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- Definition

The amount of interest capitalized to an operative builder's inventory during the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6450988&loc=d3e26243-108391

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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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.1(d))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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