Note 14 - Segment Reporting - Summary of Revenue (Details) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Revenue		$ 39,132	$ 46,117	$ 97,740	$ 129,917
Products Excluding Consumables and Skincare [Member]
Revenue	[1]	24,121	34,958	60,621	99,706
Hand Piece Refills [Member]
Revenue		2,304	2,510	6,263	7,109
Skincare [Member]
Revenue		6,829	2,847	14,506	6,230
Product [Member]
Revenue		33,254	40,315	81,390	113,045
Service [Member]
Revenue		5,878	5,802	16,350	16,872
UNITED STATES
Revenue		15,443	26,425	40,142	74,972
JAPAN
Revenue		11,497	7,511	27,176	18,142
Asia, Excluding Japan [Member]
Revenue		3,204	3,754	8,279	11,396
Europe [Member]
Revenue		2,769	1,907	6,910	7,147
Rest of World [Member]
Revenue		$ 6,219	$ 6,520	$ 15,233	$ 18,260

[1] Included in products is rental revenue of $0.2 million for the three and nine months ended September 30, 2020.