Note 11 - Marketable Securities (Tables)

3 Months Ended

Mar. 31, 2021

Notes Tables

Marketable Securities [Table Text Block]

	March 31, 2021						December 31, 2020
			Unrealized		Fair				Unrealized		Fair
	Cost		Gains (Losses)		Value		Cost		Gains (Losses)		Value
Certificates of deposit - Current marketable securities	$	26	$	—	$	26	$	21	$	—	$	21
Corporate securities - Noncurrent marketable securities	$	16	$	16	$	32	$	16	$	33	$	49