Consolidated Balance Sheets (Parentheticals) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Trade accounts receivable, allowance	$ 47	$ 17
Accumulated depreciation	1,441	1,284
Accumulated amortization	$ 11,191	$ 9,601
Preferred stock, par value (in dollars per share)	$ 0.001	$ 0.001
Preferred stock, authorized (in shares)	10,000,000	10,000,000
Preferred stock, issued (in shares)	0	0
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, shares authorized (in shares)	325,000,000	325,000,000
Common stock, shares issued (in shares)	28,383,373	28,552,886
Common stock, shares outstanding (in shares)	28,383,373	28,552,886
Treasury stock, shares (in shares)	353,063	0