Income Taxes - Additional Information (Detail) - USD ($)	3 Months Ended		12 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018	Dec. 31, 2017
Income Tax Contingency [Line Items]
Estimates annual effective tax rate	4.60%
Deferred tax benefit	$ 610,000	$ 890,000
Current tax expense	$ (610,000)	$ (890,000)
Effective tax rate	2.60%	50.20%
Unrecognized tax benefits that would affect effective tax rate	$ 0
GILTI deferred amounts				$ 0
GILTI income tax	0		$ 0
Foreign Tax Authority [Member] | TransEnterix Italia [Member]
Income Tax Contingency [Line Items]
Net deferred tax asset	0
Valuation allowance	0
Foreign Tax Authority [Member] | Israel Tax Authority [Member]
Income Tax Contingency [Line Items]
Current tax expense	$ 20,000