Restructuring charges - Charges Recognized (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 02, 2017	Jun. 26, 2016	Jul. 02, 2017	Jun. 26, 2016
Restructuring Cost and Reserve [Line Items]
Restructuring charges	$ 870	$ (119)	$ 13,815	$ 9,849
Termination Benefits
Restructuring Cost and Reserve [Line Items]
Restructuring charges	612	(609)	13,361	9,243
Facility Closure Costs
Restructuring Cost and Reserve [Line Items]
Restructuring charges	35	55	94	178
Contract Termination Costs
Restructuring Cost and Reserve [Line Items]
Restructuring charges	75	115	134	7
Other Exit Costs
Restructuring Cost and Reserve [Line Items]
Restructuring charges	148	320	226	421
2017 Vascular Solutions integration program
Restructuring Cost and Reserve [Line Items]
Restructuring charges	404		4,887
2017 Vascular Solutions integration program | Termination Benefits
Restructuring Cost and Reserve [Line Items]
Restructuring charges	370		4,853
2017 Vascular Solutions integration program | Facility Closure Costs
Restructuring Cost and Reserve [Line Items]
Restructuring charges	0		0
2017 Vascular Solutions integration program | Contract Termination Costs
Restructuring Cost and Reserve [Line Items]
Restructuring charges	0		0
2017 Vascular Solutions integration program | Other Exit Costs
Restructuring Cost and Reserve [Line Items]
Restructuring charges	34		34
2017 EMEA restructuring program
Restructuring Cost and Reserve [Line Items]
Restructuring charges	(584)		6,536
2017 EMEA restructuring program | Termination Benefits
Restructuring Cost and Reserve [Line Items]
Restructuring charges	(584)		6,536
2017 EMEA restructuring program | Facility Closure Costs
Restructuring Cost and Reserve [Line Items]
Restructuring charges	0		0
2017 EMEA restructuring program | Contract Termination Costs
Restructuring Cost and Reserve [Line Items]
Restructuring charges	0		0
2017 EMEA restructuring program | Other Exit Costs
Restructuring Cost and Reserve [Line Items]
Restructuring charges	0		0
2016 Footprint realignment plan
Restructuring Cost and Reserve [Line Items]
Restructuring charges	391		901
2016 Footprint realignment plan | Termination Benefits
Restructuring Cost and Reserve [Line Items]
Restructuring charges	286		825
2016 Footprint realignment plan | Facility Closure Costs
Restructuring Cost and Reserve [Line Items]
Restructuring charges	10		22
2016 Footprint realignment plan | Contract Termination Costs
Restructuring Cost and Reserve [Line Items]
Restructuring charges	(4)		(75)
2016 Footprint realignment plan | Other Exit Costs
Restructuring Cost and Reserve [Line Items]
Restructuring charges	99		129
2015 Restructuring programs
Restructuring Cost and Reserve [Line Items]
Restructuring charges		(247)		(10)
2015 Restructuring programs | Termination Benefits
Restructuring Cost and Reserve [Line Items]
Restructuring charges		(442)		(399)
2015 Restructuring programs | Facility Closure Costs
Restructuring Cost and Reserve [Line Items]
Restructuring charges		55		178
2015 Restructuring programs | Contract Termination Costs
Restructuring Cost and Reserve [Line Items]
Restructuring charges		115		93
2015 Restructuring programs | Other Exit Costs
Restructuring Cost and Reserve [Line Items]
Restructuring charges		25		118
2014 Footprint realignment plan
Restructuring Cost and Reserve [Line Items]
Restructuring charges	(114)		197
2014 Footprint realignment plan | Termination Benefits
Restructuring Cost and Reserve [Line Items]
Restructuring charges	(121)		182
2014 Footprint realignment plan | Facility Closure Costs
Restructuring Cost and Reserve [Line Items]
Restructuring charges	14		14
2014 Footprint realignment plan | Contract Termination Costs
Restructuring Cost and Reserve [Line Items]
Restructuring charges	0		0
2014 Footprint realignment plan | Other Exit Costs
Restructuring Cost and Reserve [Line Items]
Restructuring charges	(7)		1
Other restructuring programs
Restructuring Cost and Reserve [Line Items]
Restructuring charges	773		1,294	(80)
Other restructuring programs | Termination Benefits
Restructuring Cost and Reserve [Line Items]
Restructuring charges	661		965	0
Other restructuring programs | Facility Closure Costs
Restructuring Cost and Reserve [Line Items]
Restructuring charges	11		58	0
Other restructuring programs | Contract Termination Costs
Restructuring Cost and Reserve [Line Items]
Restructuring charges	79		209	(86)
Other restructuring programs | Other Exit Costs
Restructuring Cost and Reserve [Line Items]
Restructuring charges	$ 22		$ 62	6
2016 Footprint realignment plan
Restructuring Cost and Reserve [Line Items]
Restructuring charges		7		10,354
2016 Footprint realignment plan | Termination Benefits
Restructuring Cost and Reserve [Line Items]
Restructuring charges		(279)		10,068
2016 Footprint realignment plan | Facility Closure Costs
Restructuring Cost and Reserve [Line Items]
Restructuring charges		0		0
2016 Footprint realignment plan | Contract Termination Costs
Restructuring Cost and Reserve [Line Items]
Restructuring charges		0		0
2016 Footprint realignment plan | Other Exit Costs
Restructuring Cost and Reserve [Line Items]
Restructuring charges		286		286
2014 Footprint realignment plan
Restructuring Cost and Reserve [Line Items]
Restructuring charges		121		(415)
2014 Footprint realignment plan | Termination Benefits
Restructuring Cost and Reserve [Line Items]
Restructuring charges		112		(426)
2014 Footprint realignment plan | Facility Closure Costs
Restructuring Cost and Reserve [Line Items]
Restructuring charges		0		0
2014 Footprint realignment plan | Contract Termination Costs
Restructuring Cost and Reserve [Line Items]
Restructuring charges		0		0
2014 Footprint realignment plan | Other Exit Costs
Restructuring Cost and Reserve [Line Items]
Restructuring charges		$ 9		$ 11