Note 2 - Summary of Significant Accounting Policies - Weighted Average Common Shares (Details) - shares	3 Months Ended														12 Months Ended
	Dec. 31, 2020	[1]	Sep. 30, 2020	[2]	Jun. 30, 2020	[3]	Mar. 31, 2020	[4]	Dec. 31, 2019	Sep. 30, 2019	[5]	Jun. 30, 2019	[6]	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019
Weighted average common shares outstanding–basic (in shares)	10,282,903		10,269,995		10,252,490		10,220,853		10,274,980	10,421,383		10,411,276		10,385,017	10,256,560	10,373,164
Unvested shares of restricted stock and employee stock options (in shares)																18,811
Weighted average common shares and common share equivalents outstanding – diluted (in shares)	10,282,903		10,287,562		10,258,917		10,220,853		10,298,535	10,429,536		10,411,276		10,414,330	10,256,560	10,391,975
Average number of potentially dilutive securities excluded from calculation (in shares)															717,015	523,485

[1] The quarter ended December 31, 2020 includes $1,078 of restructuring and other charges which are discussed in Note 3.

[2] The quarter ended September 30, 2020 includes $161 of restructuring and other charges which are discussed in Note 3.

[3] The quarter ended June 30, 2020 includes $38 of restructuring and other charges which are discussed in Note 3.

[4] The quarter ended March 31, 2020 includes $8 of restructuring and other charges which are discussed in Note 3.

[5] The quarter ended September 30, 2019 includes $17 of restructuring and other charges which are discussed in Note 3.

[6] The quarter ended June 30, 2019 includes $223 of restructuring and other charges which are discussed in Note 3.