Net revenues Other revenues (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 01, 2018	Jul. 02, 2017	Jul. 01, 2018	Jul. 02, 2017
Revenue, Major Customer [Line Items]
Net revenues	$ 609,866	$ 528,613	$ 1,197,096	$ 1,016,494
Vascular access
Revenue, Major Customer [Line Items]
Net revenues	140,604	133,323	284,845	263,345
Anesthesia
Revenue, Major Customer [Line Items]
Net revenues	89,810	85,938	175,229	167,143
Interventional
Revenue, Major Customer [Line Items]
Net revenues	77,179	68,425	148,858	112,391
Surgical
Revenue, Major Customer [Line Items]
Net revenues	90,489	90,740	176,139	178,044
Interventional urology
Revenue, Major Customer [Line Items]
Net revenues	47,674	0	89,974	0
OEM
Revenue, Major Customer [Line Items]
Net revenues	52,594	45,132	98,448	88,478
Other (3)
Revenue, Major Customer [Line Items]
Net revenues	$ 111,516	$ 105,055	$ 223,603	$ 207,093