Goodwill, In-Process Research and Development and Intellectual Property - Additional Information (Detail) - USD ($)			3 Months Ended	9 Months Ended	12 Months Ended
	Oct. 31, 2018	Sep. 21, 2015	Sep. 30, 2019	Sep. 30, 2019	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Goodwill And Intangible Assets [Line Items]
Goodwill					$ 0	$ 80,131,000	$ 71,368,000
Accumulated impairment of goodwill					140,800,000	61,800,000
Goodwill impairment			$ 79,000,000.0	$ 79,000,000.0	78,969,000	0
In-process research and development impairment			$ 7,900,000		7,912,000	$ 0
In-Process Research and Development
Goodwill And Intangible Assets [Line Items]
Discount rate	15.00%	45.00%
In-process research and development impairment					$ 7,912,000
Technology and Patents Purchased
Goodwill And Intangible Assets [Line Items]
Weighted average remaining useful life					7 years 3 months 18 days
Developed Technology
Goodwill And Intangible Assets [Line Items]
Weighted average remaining useful life					2 years 9 months 18 days
Safe Stitch Medical Inc
Goodwill And Intangible Assets [Line Items]
Goodwill					$ 93,800,000
Senhance Surgical Robotic System Acquisition
Goodwill And Intangible Assets [Line Items]
Goodwill					38,300,000
Senhance Surgical Robotic System Acquisition | In-Process Research and Development
Goodwill And Intangible Assets [Line Items]
In-process research and development		$ 17,100,000
Medical Surgery Technologies Ltd.
Goodwill And Intangible Assets [Line Items]
Goodwill	$ 9,638,000				$ 9,600,000
Medical Surgery Technologies Ltd. | In-Process Research and Development
Goodwill And Intangible Assets [Line Items]
In-process research and development	$ 10,600,000