Note 12 - Stockholders' Equity (Details Textual) $ in Millions		12 Months Ended
	Jul. 15, 2021 shares	Dec. 31, 2021 shares	Dec. 31, 2020 shares	Dec. 31, 2016	Jul. 31, 2012 USD ($)
Excess Stock, Shares Authorized (in shares)		1,000,000
Preferred Stock, Shares Outstanding, Ending Balance (in shares)		0
Incremental Common Shares Attributable to Share-based Payment Arrangements, Total (in shares)		35,000	35,000
Stock Issued During Period, Fractional Shares, Stock Splits (in shares)	0
Reverse Stock Split, Fractional Shares, Cash, Multiplier	0.70
Reverse Stock Split [Member]
Stockholders' Equity Note, Stock Split, Conversion Ratio	12
Minimum [Member]
Equity Method Investment, Ownership Percentage				4.90%
Privately Negotiated Transaction [Member] | Common Stock [Member]
Stock Repurchase Program, Authorized Amount | $					$ 5
Stock Repurchased During Period, Shares (in shares)		0	0