Note 1 - Summary of Significant Accounting Policies - Other Intangible Assets (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2020	Dec. 31, 2019
Gross carrying amount	$ 2,277	$ 2,272
Accumulated amortization	980	929
Other Intangible Assets, Net	$ 1,297	$ 1,343	[1]
Customer Relationships [Member]
Remaining lives (Year)	9 years	9 years
Gross carrying amount	$ 1,302	$ 1,302
Accumulated amortization	687	651
Other Intangible Assets, Net	$ 615	$ 651
Intellectual Property [Member]
Remaining lives (Year)	3 years	3 years
Gross carrying amount	$ 100	$ 100
Accumulated amortization	100	95
Other Intangible Assets, Net		$ 5
Trade Names [Member]
Remaining lives (Year)	20 years	20 years
Gross carrying amount	$ 814	$ 814
Accumulated amortization	193	183
Other Intangible Assets, Net	$ 621	$ 631
Patents [Member]
Remaining lives (Year)	7 years	7 years
Gross carrying amount	$ 61	$ 56
Accumulated amortization
Other Intangible Assets, Net	$ 61	$ 56

[1] The balance sheet at December 31, 2019 has been derived from the audited financial statements at that date