BASIS OF PRESENTATION - Breakdown of net revenue (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Device revenue
Total Device revenue	$ 34,786	$ 20,026	$ 89,935	$ 54,517
Devices [Member]
Device revenue
Purchased	2,076	1,618	6,734	4,121
Leased	6,995	3,683	16,530	8,905
Total Device revenue	$ 9,071	$ 5,301	$ 23,264	$ 13,026