Note 17 - Share-based Compensation - Number of Shares to Be Issued Upon Exercise of Outstanding Stock-based Awards (Details)	Dec. 31, 2019 shares
Expected shares to be awarded (in shares)	547,000
Number of shares to be issued upon exercise (in shares)	118,000
Stock Appreciation Rights (SARs) [Member]
Expected shares to be awarded (in shares)	547,000	[1]
Restricted Stock [Member]
Number of shares to be issued upon exercise (in shares)	108,000
Restricted Stock Units (RSUs) [Member]
Number of shares to be issued upon exercise (in shares)	10,000

[1] Under the 2015 Omnibus Equity Compensation Plan, shares of stock are authorized for issuance as incentive and non-qualified stock options, SARs, RSAs, and RSUs.