Share Capital - Schedule of Non-cash Share-Based Compensation Expenses Related to Company's Equity-Based Awards (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total share-based compensation expense	$ 9,649	$ 8,520	$ 39,846
Cost of Revenues
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total share-based compensation expense	426	164	1,261
Research, Development and Clinical Trials
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total share-based compensation expense	1,188	906	4,709
Sales and Marketing
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total share-based compensation expense	1,962	1,436	7,393
General and Administrative
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total share-based compensation expense	$ 6,073	$ 6,014	$ 26,483