Note 10 - Dividends Payable (Details Textual) - USD ($)	3 Months Ended
	Mar. 31, 2018	Apr. 30, 2018	Mar. 31, 2017
Dividends Payable	$ 36,000		$ 35,000
Preferred Stock [Member]
Dividends Payable	483,000		$ 447,000
Series 1 Preferred Stock [Member]
Dividends, Preferred Stock, Total	$ 12,000
Preferred Stock, Dividend Rate, Percentage	5.00%
Series 2 Preferred Stock [Member]
Dividends, Preferred Stock, Total	$ 15,000
Preferred Stock, Dividend Rate, Percentage	5.00%
Series 3 Preferred Stock [Member]
Dividends, Preferred Stock, Total	$ 9,000
Preferred Stock, Dividend Rate, Percentage	5.00%
Series 2 Preferred Stock and Series 3 Preferred Stock [Member]
Preferred Stock Unpaid Dividends Additional Late Fee Penalty Percentage	18.00%
Period From Issuance of Written Notice For Failure to Pay Dividend Within Which Entity Must Cure Breach	45 days
Series 2 Preferred Stock and Series 3 Preferred Stock [Member] | Subsequent Event [Member]
Preferred Stock, Redemption Amount		$ 2,400,000