Note 1 - Organization and Summary of Significant Accounting Policies (Details Textual)		1 Months Ended	3 Months Ended		4 Months Ended	12 Months Ended
	May 08, 2020 $ / shares shares	May 07, 2020 USD ($) shares	Mar. 31, 2020 USD ($) $ / shares shares	Mar. 31, 2019 USD ($) shares	May 07, 2020 USD ($) $ / shares shares	Dec. 31, 2019 USD ($) $ / shares	Jun. 28, 2019 USD ($)
Entity Public Float							$ 58,900,000
Common Stock, Par or Stated Value Per Share (in dollars per share) | $ / shares			$ 0.01			$ 0.01
Restricted Cash, Total			$ 424,000	$ 116,000		$ 117,000
Impairment of Real Estate			0	0
Abandoned Project Costs			14,036,000	$ 5,000
Nonrefundable Cash Deposits			13,600,000
Stockholders' Equity Attributable to Noncontrolling Interest, Ending Balance			$ 112,000			112,000
Capitalized Contract Cost, Amortization Period (Month)			30 months
Period of General Warranty (Year)			1 year
Accounts Receivable, Allowance for Credit Loss, Ending Balance			$ 0			$ 0
Capitalized Selling and Marketing Cost, Amortization Period (Month)			30 months
Deferred Tax Assets, Valuation Allowance, Total			$ 0
Unrecognized Tax Benefits, Ending Balance			0
Income Tax Examination, Penalties and Interest Accrued, Total			$ 0
Stock Repurchased and Retired During Period, Shares (in shares) | shares			1,233,883	153,916	2,011,183
Stock Repurchased and Retired During Period, Value			$ 2,233,000	$ 1,042,000	$ 3,600,000
Stock Repurchased and Retired During Period, Weighted Average Purchase Price (in dollars per share) | $ / shares					$ 1.78
Stock Repurchased and Retired, Percent of Intial Outstanding Stock					10.00%
Dividends, Common Stock, Total			0	0
Unconsolidated Joint Ventures [Member]
Equity Method Investment, Other than Temporary Impairment			$ 2,300,000	0
Maximum [Member]
Property, Plant and Equipment, Useful Life (Year)			5 years
Maximum [Member] | Unconsolidated Joint Ventures [Member]
Equity Method Investment, Ownership Percentage			35.00%			35.00%
Minimum [Member]
Limited Warranty Period (Year)			2 years
Property, Plant and Equipment, Useful Life (Year)			3 years
Minimum [Member] | Unconsolidated Joint Ventures [Member]
Equity Method Investment, Ownership Percentage			5.00%			5.00%
Noncontrolling Interest [Member]
Stockholders' Equity Attributable to Noncontrolling Interest, Ending Balance			$ 100,000			$ 100,000
Stock Repurchased and Retired During Period, Value			$ (0)	$ (0)
Customer Concentration Risk [Member] | Fee Building Revenue [Member]
Number of Major Customers			4	1
Concentration Risk, Percentage			98.00%	91.00%
Customer Concentration Risk [Member] | Accounts Receivable [Member]
Number of Major Customers			4			1
Customer Concentration Risk [Member] | Accounts Receivable [Member] | One Customer [Member]
Concentration Risk, Percentage			73.00%			65.00%
Subsequent Event [Member]
Common Stock, Par or Stated Value Per Share (in dollars per share) | $ / shares	$ 0.01
Stock Repurchased and Retired During Period, Shares (in shares) | shares		777,300
Stock Repurchased and Retired During Period, Value		$ 1,400,000
Stock Repurchase Program, Remaining Authorized Repurchase Amount		$ 1,800,000			$ 1,800,000
Subsequent Event [Member] | Preferred Stock Purchase Right [Member]
Dividend, Stock Awarded Per Share (in shares) | shares	1
Preferred Stock, Convertible, Conversion Price (in dollars per share) | $ / shares	$ 11.50
Preferred Stock, Minimum Threshold Percent of Common Stock Ownership Required for Exercise	4.95%
Convertible Preferred Stock, Shares Issued upon Conversion (in shares) | shares	1