Net revenues Other revenues (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Oct. 01, 2017	Sep. 30, 2018	Oct. 01, 2017
Revenue, Major Customer [Line Items]
Net revenues	$ 609,672	$ 534,703	$ 1,806,768	$ 1,551,197
Vascular access
Revenue, Major Customer [Line Items]
Net revenues	142,712	133,521	427,557	396,866
Anesthesia
Revenue, Major Customer [Line Items]
Net revenues	87,973	87,964	263,202	255,107
Interventional
Revenue, Major Customer [Line Items]
Net revenues	79,404	69,186	228,262	181,577
Surgical
Revenue, Major Customer [Line Items]
Net revenues	89,910	85,210	266,049	263,254
Interventional urology
Revenue, Major Customer [Line Items]
Net revenues	48,995	0	138,969	0
OEM
Revenue, Major Customer [Line Items]
Net revenues	54,838	48,589	153,286	137,067
Other (3)
Revenue, Major Customer [Line Items]
Net revenues	$ 105,840	$ 110,233	$ 329,443	$ 317,326