Note 3 - Equity (Details Textual) - USD ($)		3 Months Ended		9 Months Ended
	Aug. 31, 2021	Sep. 30, 2021	Aug. 18, 2021	Sep. 30, 2021	Jun. 30, 2021	May 09, 2019
Preferred Stock, Shares Authorized (in shares)		30,000,000		30,000,000	30,000,000
Preferred Stock, Par or Stated Value Per Share (in dollars per share)		$ 0.01		$ 0.01	$ 0.01
Stock Repurchase Program, Authorized Amount			$ 6,000,000.0			$ 4,000,000.0
Stock Repurchase Program, Period in Force (Month)			24 months
Stock Repurchase Program, Increase in Authorized Amount	$ 10,000,000
Stock Repurchase Program, Remaining Authorized Repurchase Amount		$ 12,009,609		$ 12,009,609
Preferred Stock, Shares Outstanding, Ending Balance (in shares)		19,387,552		19,387,552	19,351,935
Blank Check [Member]
Preferred Stock, Shares Authorized (in shares)		30,000,000		30,000,000
Preferred Stock, Par or Stated Value Per Share (in dollars per share)		$ 0.01		$ 0.01
Series B Preferred Stock [Member]
Preferred Stock, Shares Authorized (in shares)		700,000		700,000	700,000
Preferred Stock, Shares, Number (in shares)		700,000
Preferred Stock, Shares Issued, Total (in shares)		625,375		625,375	625,375
Preferred Stock, Shares Outstanding, Ending Balance (in shares)		625,375		625,375	625,375
Series B-1 Preferred Stock [Member]
Preferred Stock, Shares Authorized (in shares)		550,000		550,000	550,000
Preferred Stock, Shares, Number (in shares)		550,000
Preferred Stock, Cash, Dividend Rate, Percentage		7.00%
Preferred Stock, Series B Preferred Shares, Dividend Rate, Percentage		9.00%
Preferred Stock, Redemption Price Per Share (in dollars per share)		$ 10.70		$ 10.70
Preferred Stock, Shares Issued, Total (in shares)		212,402		212,402	212,402
Preferred Stock, Shares Outstanding, Ending Balance (in shares)		212,402		212,402	212,402
Share-based Payment Arrangement, Nonemployee [Member]
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total		$ 4,600,000		$ 4,600,000
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)				2 years 2 months 26 days
Restricted Stock Units (RSUs) [Member] | Share-based Payment Arrangement, Nonemployee [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding, Number, Ending Balance (in shares)		856,168		856,168
Restricted Stock Units (RSUs) [Member] | Vested and Unissued [Member] | Share-based Payment Arrangement, Nonemployee [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding, Number, Ending Balance (in shares)		9,288		9,288