Note 4 - Debt (Tables)

3 Months Ended

Mar. 31, 2019

Notes Tables

Schedule of Long-term Debt Instruments [Table Text Block]

	March 31, 2019				December 31, 2018
	Principal		Carrying Amount		Principal		Carrying Amount
2017 Senior Credit Facility	$	32,000	$	32,000	$	27,000	$	27,000
Convertible Second Lien Notes (1)		55,493		52,969		53,691		49,820
Total debt	$	87,493	$	84,969	$	80,691	$	76,820

Schedule of Interest Expense and Effective Interest on Liability Component [Table Text Block]

	Three Months Ended March 31, 2019					Three Months Ended March 31, 2018
	Interest Expense		Effective Interest Rate			Interest Expense		Effective Interest Rate
2017 Senior Credit Facility	$	508		6.7	%	$	173		6.3	%
Convertible Second Lien Notes (1)		3,149		24.3	%		2,500		24.6	%
Total interest expense	$	3,657				$	2,673