Note 4 - Real Estate Under Development (Details Textual) - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Real Estate Under Development, Capitalized Costs of Interest, Real Estate Taxes, Insurance, Legal Costs and Payroll	$ 27.4		$ 24.9
Impairment of Real Estate	41.2	$ 33.9
Real Estate Inventory, Capitalized Interest Costs Incurred	6.6
Real Estate Development Projects, Real Estate Taxes and Insurance Capitalized	1.1
Real Estate Development Projects, Payroll Costs Capitalized	1.1
Promenade at Christiana [Member]
Impairment of Real Estate	$ 11.5

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.

+ 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.

+ Details

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- Definition

The charge against earnings in the period to reduce the carrying amount of real property to fair value.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3602-108585

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109226691&loc=d3e2921-110230

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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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- Details

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