Note 5 - Accounts Receivable (Tables)

3 Months Ended

Mar. 31, 2020

Notes Tables

Schedule of Accounts, Notes, Loans and Financing Receivable [Table Text Block]

	March 31,		December 31,
	2020		2019
Royalties	$	4,789	$	4,304
Product sales, license and other		1,401		11,672
Accounts receivable, net	$	6,190	$	15,976