CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Income Statement [Abstract]
Net revenues	$ 61,514	$ 38,376	$ 113,639	$ 73,256	$ 177,026
Cost of revenues	19,833	13,152	38,071	24,816	55,609
Gross profit	41,681	25,224	75,568	48,440	121,417
Operating costs and expenses:
Research, development and clinical trials	11,362	9,371	22,466	18,782	38,103
Sales and marketing	19,196	16,360	37,331	31,116	63,528
General and administrative	18,208	15,023	35,533	27,445	59,114
Total operating costs and expenses	48,766	40,754	95,330	77,343	160,745
Operating loss	(7,085)	(15,530)	(19,762)	(28,903)	(39,328)
Financial expenses, net	2,860	2,183	7,713	4,629	9,169
Loss before income taxes	(9,945)	(17,713)	(27,475)	(33,532)	(48,497)
Income taxes	5,565	3,461	8,759	5,687	13,165
Net loss	$ (15,510)	$ (21,174)	$ (36,234)	$ (39,219)	$ (61,662)
Basic and diluted net loss per ordinary share	$ (0.17)	$ (0.24)	$ (0.40)	$ (0.45)	$ (0.70)
Weighted average number of ordinary shares used in computing basic and diluted net loss per share	91,331,862	88,218,868	90,658,735	87,835,926	88,546,719