REVENUE AND DEFERRED REVENUE - Summary of Revenue Generated in Product Category for Years Indicated (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Segment Reporting Information [Line Items]
Revenues	$ 17,417	$ 15,540
Product Category | U.S. | Revenue
Segment Reporting Information [Line Items]
Revenues	$ 16,793	$ 14,964
Percentage of Revenues	100.00%	100.00%
Product Category | U.S. | Revenue | NeuroStar Advanced Therapy System
Segment Reporting Information [Line Items]
Revenues	$ 3,310	$ 3,850
Percentage of Revenues	20.00%	26.00%
Product Category | U.S. | Revenue | Treatment Sessions
Segment Reporting Information [Line Items]
Revenues	$ 12,988	$ 10,643
Percentage of Revenues	77.00%	71.00%
Product Category | U.S. | Revenue | Other
Segment Reporting Information [Line Items]
Revenues	$ 495	$ 471
Percentage of Revenues	3.00%	3.00%
Product Category | International | Revenue
Segment Reporting Information [Line Items]
Revenues	$ 624	$ 576
Percentage of Revenues	100.00%	100.00%
Product Category | International | Revenue | NeuroStar Advanced Therapy System
Segment Reporting Information [Line Items]
Revenues	$ 258	$ 259
Percentage of Revenues	41.00%	45.00%
Product Category | International | Revenue | Treatment Sessions
Segment Reporting Information [Line Items]
Revenues	$ 172	$ 184
Percentage of Revenues	28.00%	32.00%
Product Category | International | Revenue | Other
Segment Reporting Information [Line Items]
Revenues	$ 194	$ 133
Percentage of Revenues	31.00%	23.00%