Segment Reporting and Geographic Information - Summary of Net Sales and Net Operating Loss by Reportable Segment (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Segment Reporting Information [Line Items]
Total net sales	$ 36,542	$ 20,734	$ 38,106
Total loss from operations	(62,890)	(40,034)	(38,525)
Breast Product
Segment Reporting Information [Line Items]
Total net sales	31,485	20,734	38,106
Total loss from operations	(56,657)	$ (40,034)	$ (38,525)
miraDry
Segment Reporting Information [Line Items]
Total net sales	5,057
Total loss from operations	$ (6,233)