Note 7 - Commitments and Contingencies - Share-based Compensation Arrangements (Details) - Chief Executive Officer [Member] - The 2016 Employee Equity Compensation Restricted Stock Plan [Member]	Aug. 30, 2021 $ / shares shares
Performance Restricted Stock Price Hurdle1 [Member]
Absolute Stock Price Hurdle (in dollars per share) | $ / shares	$ 40
Shares (in shares)	85,000
Cumulative Shares (in shares)	85,000
Performance Restricted Stock Price Hurdle 2 [Member]
Absolute Stock Price Hurdle (in dollars per share) | $ / shares	$ 45
Shares (in shares)	107,000
Cumulative Shares (in shares)	192,000
Performance Restricted Stock Price Hurdle 3 [Member]
Absolute Stock Price Hurdle (in dollars per share) | $ / shares	$ 50
Shares (in shares)	106,000
Cumulative Shares (in shares)	298,000
Performance Restricted Stock Price Hurdle 4 [Member]
Absolute Stock Price Hurdle (in dollars per share) | $ / shares	$ 55
Shares (in shares)	106,000
Cumulative Shares (in shares)	404,000
Performance Restricted Stock Price Hurdle 5 [Member]
Absolute Stock Price Hurdle (in dollars per share) | $ / shares	$ 60
Shares (in shares)	106,000
Cumulative Shares (in shares)	510,000