Note 9 - Commitments and Contingencies (Tables)

6 Months Ended

Jun. 30, 2019

Notes Tables

Schedule of Product Warranty Liability [Table Text Block]

	Three Months Ended June 30,						Six Months Ended June 30,
	2019			2018			2019			2018
Balance at beginning of period	$	2,045		$	3,740		$	4,564		$	2,416
Warranty provision for product sales		311			335			579			1,814
Settlements made		(28	)		(9	)		(2,299	)		(64	)
Unused warranty provision		(580	)		(115	)		(1,096	)		(215	)
Balance at end of period	$	1,748		$	3,951		$	1,748		$	3,951