Inventories - Schedule of Inventory (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Mar. 31, 2020
Inventory Disclosure [Abstract]
Finished goods	$ 9,737	$ 9,296
Raw materials	8,510	7,734
Total inventories	18,247	17,030
Current portion	10,653	9,829
Long-term portion	7,594	$ 7,201
Inventory [Line Items]
Inventory write-down related to restructuring	7,400
Surgi Bot System
Inventory [Line Items]
Write down of inventory	$ 1,500