Note 10 - Revenues - Summary of Disaggregation of Revenues (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Disaggregation Of Revenue [Line Items]
Rental Income	$ 242
Sublease income	47	$ 93
Total Out of Scope of Topic 606 revenue	289	93
Total revenues	7,242	5,935
Accounting Standards Update 2014-09 [Member]
Disaggregation Of Revenue [Line Items]
Topic 606 Revenue	6,953	5,842
Leasing Commissions [Member] \| Accounting Standards Update 2014-09 [Member] \| Point in Time [Member]
Disaggregation Of Revenue [Line Items]
Topic 606 Revenue	4,466	3,139
Property and Asset Management Fees [Member] \| Accounting Standards Update 2014-09 [Member] \| Over Time [Member]
Disaggregation Of Revenue [Line Items]
Topic 606 Revenue	1,602	1,534
Engineering Services [Member] \| Accounting Standards Update 2014-09 [Member] \| Over Time [Member]
Disaggregation Of Revenue [Line Items]
Topic 606 Revenue	513	453
Guaranty Fees [Member] \| Accounting Standards Update 2014-09 [Member] \| Over Time [Member]
Disaggregation Of Revenue [Line Items]
Topic 606 Revenue	30	31
Development Fees [Member] \| Accounting Standards Update 2014-09 [Member] \| Over Time [Member]
Disaggregation Of Revenue [Line Items]
Topic 606 Revenue	225	101
Sales Commissions [Member] \| Accounting Standards Update 2014-09 [Member] \| Point in Time [Member]
Disaggregation Of Revenue [Line Items]
Topic 606 Revenue		337
Equity Fees [Member] \| Accounting Standards Update 2014-09 [Member] \| Point in Time [Member]
Disaggregation Of Revenue [Line Items]
Topic 606 Revenue	$ 117	166
Acquisition and Disposition Fees [Member] \| Accounting Standards Update 2014-09 [Member] \| Point in Time [Member]
Disaggregation Of Revenue [Line Items]
Topic 606 Revenue		$ 81

Rental income.

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+ References

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Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Amount of revenue that is not accounted for under Topic 606.

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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Amount of sublease income excluding finance and operating lease expense.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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