Restructuring charges - additional information (Detail) - USD ($)	3 Months Ended		9 Months Ended		13 Months Ended	17 Months Ended	19 Months Ended	33 Months Ended
	Sep. 27, 2015	Sep. 28, 2014	Sep. 27, 2015	Sep. 28, 2014	Jun. 28, 2015	Sep. 27, 2015	Sep. 27, 2015	Sep. 27, 2015
Restructuring Cost And Reserve [Line Items]
Restructuring charges	$ 660,000	$ 1,108,000	$ 5,688,000	$ 16,511,000
Impairment charges	0	0	0	0
Facility Closure Costs
Restructuring Cost And Reserve [Line Items]
Restructuring charges	34,000	1,000	409,000	255,000
Contract Termination Costs
Restructuring Cost And Reserve [Line Items]
Restructuring charges	241,000	409,000	1,141,000	(1,286,000)
Other
Restructuring Cost And Reserve [Line Items]
Restructuring charges	61,000	131,000	127,000	333,000
2015 Restructuring Program
Restructuring Cost And Reserve [Line Items]
Restructuring charges	(74,000)		4,306,000
Restructuring reserve	2,900,000		2,900,000			$ 2,900,000	$ 2,900,000	$ 2,900,000
2015 Restructuring Program | Facility Closure Costs
Restructuring Cost And Reserve [Line Items]
Restructuring charges	37,000		166,000
2015 Restructuring Program | Contract Termination Costs
Restructuring Cost And Reserve [Line Items]
Restructuring charges	78,000		723,000
2015 Restructuring Program | Other
Restructuring Cost And Reserve [Line Items]
Restructuring charges	9,000		56,000
2015 Restructuring Program | Minimum
Restructuring Cost And Reserve [Line Items]
Expected restructuring charges	6,000,000		6,000,000			6,000,000	6,000,000	6,000,000
2015 Restructuring Program | Maximum
Restructuring Cost And Reserve [Line Items]
Expected restructuring charges	7,000,000		7,000,000			7,000,000	7,000,000	7,000,000
2014 Manufacturing Footprint Realignment Plan
Restructuring Cost And Reserve [Line Items]
Restructuring charges	831,000	171,000	1,497,000	8,748,000
Restructuring reserve	7,500,000		7,500,000			7,500,000	7,500,000	7,500,000
Restructuring expenses	3,200,000		9,100,000			10,800,000
2014 Manufacturing Footprint Realignment Plan | Accelerated Depreciation And Other Costs
Restructuring Cost And Reserve [Line Items]
Restructuring expenses						12,400,000
Restructuring cost related to accelerated depreciation	2,400,000		7,600,000
2014 Manufacturing Footprint Realignment Plan | Facility Closure Costs
Restructuring Cost And Reserve [Line Items]
Restructuring charges	(3,000)	0	241,000	0
2014 Manufacturing Footprint Realignment Plan | Contract Termination Costs
Restructuring Cost And Reserve [Line Items]
Restructuring charges	163,000	0	389,000	0
2014 Manufacturing Footprint Realignment Plan | Other
Restructuring Cost And Reserve [Line Items]
Restructuring charges	52,000	42,000	36,000	42,000
2014 Manufacturing Footprint Realignment Plan | Minimum
Restructuring Cost And Reserve [Line Items]
Expected restructuring charges	37,000,000		37,000,000			37,000,000	37,000,000	37,000,000
Restructuring costs expected cash payment	26,000,000		26,000,000			26,000,000	26,000,000	26,000,000
2014 Manufacturing Footprint Realignment Plan | Minimum | Employee Termination Benefits
Restructuring Cost And Reserve [Line Items]
Expected restructuring charges	11,000,000		11,000,000			11,000,000	11,000,000	11,000,000
2014 Manufacturing Footprint Realignment Plan | Minimum | Facility Closure Costs
Restructuring Cost And Reserve [Line Items]
Expected restructuring charges	2,000,000		2,000,000			2,000,000	2,000,000	2,000,000
2014 Manufacturing Footprint Realignment Plan | Minimum | Accelerated Depreciation Charges
Restructuring Cost And Reserve [Line Items]
Expected restructuring charges	10,000,000		10,000,000			10,000,000	10,000,000	10,000,000
2014 Manufacturing Footprint Realignment Plan | Minimum | Other
Restructuring Cost And Reserve [Line Items]
Expected restructuring charges	14,000,000		14,000,000			14,000,000	14,000,000	14,000,000
2014 Manufacturing Footprint Realignment Plan | Maximum
Restructuring Cost And Reserve [Line Items]
Expected restructuring charges	44,000,000		44,000,000			44,000,000	44,000,000	44,000,000
Restructuring costs expected cash payment	31,000,000		31,000,000			31,000,000	31,000,000	31,000,000
2014 Manufacturing Footprint Realignment Plan | Maximum | Employee Termination Benefits
Restructuring Cost And Reserve [Line Items]
Expected restructuring charges	13,000,000		13,000,000			13,000,000	13,000,000	13,000,000
2014 Manufacturing Footprint Realignment Plan | Maximum | Facility Closure Costs
Restructuring Cost And Reserve [Line Items]
Expected restructuring charges	3,000,000		3,000,000			3,000,000	3,000,000	3,000,000
2014 Manufacturing Footprint Realignment Plan | Maximum | Accelerated Depreciation Charges
Restructuring Cost And Reserve [Line Items]
Expected restructuring charges	11,000,000		11,000,000			11,000,000	11,000,000	11,000,000
2014 Manufacturing Footprint Realignment Plan | Maximum | Other
Restructuring Cost And Reserve [Line Items]
Expected restructuring charges	17,000,000		17,000,000			17,000,000	17,000,000	17,000,000
2014 European Restructuring Plan
Restructuring Cost And Reserve [Line Items]
Restructuring charges	(97,000)	566,000	(53,000)	8,672,000
Restructuring reserve	300,000		300,000			300,000	300,000	300,000
Restructuring expenses							7,800,000
2014 European Restructuring Plan | Facility Closure Costs
Restructuring Cost And Reserve [Line Items]
Restructuring charges	0	1,000	0	1,000
2014 European Restructuring Plan | Contract Termination Costs
Restructuring Cost And Reserve [Line Items]
Restructuring charges	0	1,000	0	306,000
2014 European Restructuring Plan | Other
Restructuring Cost And Reserve [Line Items]
Restructuring charges	0	27,000	34,000	76,000
Other 2014 Restructuring Programs
Restructuring Cost And Reserve [Line Items]
Restructuring charges		289,000	49,000	2,070,000	$ 3,600,000
Restructuring reserve	300,000		300,000			300,000	300,000	300,000
Other 2014 Restructuring Programs | Facility Closure Costs
Restructuring Cost And Reserve [Line Items]
Restructuring charges		0	0	0
Other 2014 Restructuring Programs | Contract Termination Costs
Restructuring Cost And Reserve [Line Items]
Restructuring charges		202,000	49,000	1,376,000
Other 2014 Restructuring Programs | Other
Restructuring Cost And Reserve [Line Items]
Restructuring charges		62,000	0	193,000
Other 2014 Restructuring Programs | Maximum
Restructuring Cost And Reserve [Line Items]
Expected restructuring charges	$ 4,000,000		4,000,000			$ 4,000,000	$ 4,000,000	4,000,000
LMA Restructuring Program
Restructuring Cost And Reserve [Line Items]
Restructuring charges		20,000	(17,000)	(3,352,000)				11,300,000
LMA Restructuring Program | Facility Closure Costs
Restructuring Cost And Reserve [Line Items]
Restructuring charges		0	2,000	(112,000)
LMA Restructuring Program | Contract Termination Costs
Restructuring Cost And Reserve [Line Items]
Restructuring charges		20,000	(20,000)	(3,211,000)
LMA Restructuring Program | Other
Restructuring Cost And Reserve [Line Items]
Restructuring charges		0	1,000	0
2013 Restructuring Program
Restructuring Cost And Reserve [Line Items]
Restructuring charges		62,000	(94,000)	626,000				$ 11,000,000
2013 Restructuring Program | Facility Closure Costs
Restructuring Cost And Reserve [Line Items]
Restructuring charges		0	0	0
2013 Restructuring Program | Contract Termination Costs
Restructuring Cost And Reserve [Line Items]
Restructuring charges		186,000	0	243,000
2013 Restructuring Program | Other
Restructuring Cost And Reserve [Line Items]
Restructuring charges		$ 0	$ 0	$ 22,000