Revenue from Contracts with Customers - Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Disaggregation of Revenue [Line Items]
Net sales	$ 221,659	$ 179,337	$ 649,504	$ 536,955
United States
Disaggregation of Revenue [Line Items]
Net sales	126,108	103,091	360,610	313,314
International
Disaggregation of Revenue [Line Items]
Net sales	95,551	76,246	288,894	223,641
Cardiovascular
Disaggregation of Revenue [Line Items]
Net sales	212,150	172,723	624,392	517,140
Cardiovascular | United States
Disaggregation of Revenue [Line Items]
Net sales	116,879	96,702	336,341	294,119
Cardiovascular | International
Disaggregation of Revenue [Line Items]
Net sales	95,271	76,021	288,051	223,021
Endoscopy
Disaggregation of Revenue [Line Items]
Net sales	9,509	6,614	25,112	19,815
Stand-alone devices | Cardiovascular
Disaggregation of Revenue [Line Items]
Net sales	90,975	68,749	266,717	203,459
Stand-alone devices | Cardiovascular | United States
Disaggregation of Revenue [Line Items]
Net sales	52,173	36,383	147,125	109,750
Stand-alone devices | Cardiovascular | International
Disaggregation of Revenue [Line Items]
Net sales	38,802	32,366	119,592	93,709
Custom kits and procedure trays | Cardiovascular
Disaggregation of Revenue [Line Items]
Net sales	33,095	30,411	100,359	91,082
Custom kits and procedure trays | Cardiovascular | United States
Disaggregation of Revenue [Line Items]
Net sales	23,199	23,085	69,184	68,823
Custom kits and procedure trays | Cardiovascular | International
Disaggregation of Revenue [Line Items]
Net sales	9,896	7,326	31,175	22,259
Inflation devices | Cardiovascular
Disaggregation of Revenue [Line Items]
Net sales	22,893	20,033	69,617	59,329
Inflation devices | Cardiovascular | United States
Disaggregation of Revenue [Line Items]
Net sales	7,819	8,241	23,647	24,257
Inflation devices | Cardiovascular | International
Disaggregation of Revenue [Line Items]
Net sales	15,074	11,792	45,970	35,072
Catheters | Cardiovascular
Disaggregation of Revenue [Line Items]
Net sales	40,591	31,751	113,830	94,357
Catheters | Cardiovascular | United States
Disaggregation of Revenue [Line Items]
Net sales	18,081	15,377	50,055	46,529
Catheters | Cardiovascular | International
Disaggregation of Revenue [Line Items]
Net sales	22,510	16,374	63,775	47,828
Embolization devices | Cardiovascular
Disaggregation of Revenue [Line Items]
Net sales	12,395	12,252	37,706	36,936
Embolization devices | Cardiovascular | United States
Disaggregation of Revenue [Line Items]
Net sales	5,145	5,414	15,272	16,548
Embolization devices | Cardiovascular | International
Disaggregation of Revenue [Line Items]
Net sales	7,250	6,838	22,434	20,388
CRM/EP | Cardiovascular
Disaggregation of Revenue [Line Items]
Net sales	12,201	9,527	36,163	31,977
CRM/EP | Cardiovascular | United States
Disaggregation of Revenue [Line Items]
Net sales	10,462	8,202	31,058	28,212
CRM/EP | Cardiovascular | International
Disaggregation of Revenue [Line Items]
Net sales	1,739	1,325	5,105	3,765
Endoscopy devices | Endoscopy
Disaggregation of Revenue [Line Items]
Net sales	9,509	6,614	25,112	19,815
Endoscopy devices | Endoscopy | United States
Disaggregation of Revenue [Line Items]
Net sales	9,229	6,389	24,269	19,195
Endoscopy devices | Endoscopy | International
Disaggregation of Revenue [Line Items]
Net sales	$ 280	$ 225	$ 843	$ 620