Geographical Segment Information - Summary of Revenue Generated in Product Category for Years Indicated (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Segment Reporting Information [Line Items]
Revenues	$ 62,656	$ 52,776	$ 40,433
Product Category | United States | Revenues
Segment Reporting Information [Line Items]
Revenues	$ 60,760	$ 51,477	$ 39,853
Percentage of Revenues	100.00%	100.00%	100.00%
Product Category | United States | Revenues | NeuroStar Advanced Therapy System
Segment Reporting Information [Line Items]
Revenues	$ 18,007	$ 14,603	$ 10,120
Percentage of Revenues	30.00%	28.00%	25.00%
Product Category | United States | Revenues | Treatment Sessions
Segment Reporting Information [Line Items]
Revenues	$ 41,120	$ 35,287	$ 28,391
Percentage of Revenues	68.00%	69.00%	71.00%
Product Category | United States | Revenues | Other
Segment Reporting Information [Line Items]
Revenues	$ 1,633	$ 1,587	$ 1,342
Percentage of Revenues	2.00%	3.00%	4.00%
Product Category | International | Revenues
Segment Reporting Information [Line Items]
Revenues	$ 1,896	$ 1,299	$ 580
Percentage of Revenues	100.00%	100.00%	100.00%
Product Category | International | Revenues | NeuroStar Advanced Therapy System
Segment Reporting Information [Line Items]
Revenues	$ 1,106	$ 635	$ 259
Percentage of Revenues	58.00%	49.00%	45.00%
Product Category | International | Revenues | Treatment Sessions
Segment Reporting Information [Line Items]
Revenues	$ 347	$ 245	$ 230
Percentage of Revenues	18.00%	19.00%	40.00%
Product Category | International | Revenues | Other
Segment Reporting Information [Line Items]
Revenues	$ 443	$ 419	$ 91
Percentage of Revenues	24.00%	32.00%	15.00%