Condensed consolidating guarantor financial information Condensed consolidating statements of income and comprehensive income (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 28, 2015	Jun. 29, 2014	Jun. 28, 2015	Jun. 29, 2014
Condensed Income Statements, Captions [Line Items]
Net revenues	$ 452,045	$ 468,105	$ 881,475	$ 906,651
Cost of goods sold	218,808	224,017	425,601	441,404
Gross profit	233,237	244,088	455,874	465,247
Selling, general and administrative expenses	142,228	146,843	281,925	287,140
Research and development expenses	13,443	14,870	26,327	28,932
Restructuring and impairment charges	580	7,623	5,028	15,403
Income from continuing operations before interest, extinguishment of debt and taxes	76,986	74,752	142,594	133,772
Interest, net	16,053	15,916	33,056	31,133
Interest income	154	146	323	333
Loss on extinguishment of debt, net	10,454	0	10,454	0
Income from continuing operations before taxes	50,479	58,836	99,084	102,639
(Benefit) taxes on income from continuing operations	5,280	10,006	14,612	18,540
Equity in net income of consolidated subsidiaries	0	0	0	0
Income from continuing operations	45,199	48,830	84,472	84,099
Operating loss from discontinued operations	(145)	(1,594)	(644)	(1,619)
Taxes on loss from discontinued operations	45	(469)	249	(369)
Loss from discontinued operations	(190)	(1,125)	(893)	(1,250)
Net income	45,009	47,705	83,579	82,849
Less: Income from continuing operations attributable to noncontrolling interests	446	453	664	639
Net income attributable to common shareholders	44,563	47,252	82,915	82,210
Other comprehensive income attributable to common shareholders	20,986	1,862	(60,215)	6,607
Comprehensive income attributable to common shareholders	65,549	49,114	22,700	88,817
Consolidation, Eliminations
Condensed Income Statements, Captions [Line Items]
Net revenues	(93,916)	(139,826)	(187,548)	(212,142)
Cost of goods sold	(92,265)	(129,020)	(181,416)	(201,874)
Gross profit	(1,651)	(10,806)	(6,132)	(10,268)
Selling, general and administrative expenses	(243)	108	(83)	311
Research and development expenses	0	0	0	0
Restructuring and impairment charges	0	0	0	0
Income from continuing operations before interest, extinguishment of debt and taxes	(1,408)	(10,914)	(6,049)	(10,579)
Interest, net	0		0
Loss on extinguishment of debt, net	0		0
Income from continuing operations before taxes	(1,408)	(10,914)	(6,049)	(10,579)
(Benefit) taxes on income from continuing operations	(159)	(2,163)	(1,270)	(4,259)
Equity in net income of consolidated subsidiaries	(131,332)	(136,150)	(260,657)	(243,476)
Income from continuing operations	(132,581)	(144,901)	(265,436)	(249,796)
Operating loss from discontinued operations	0	0	0	0
Taxes on loss from discontinued operations	0	0	0	0
Loss from discontinued operations	0	0	0	0
Net income	(132,581)	(144,901)	(265,436)	(249,796)
Less: Income from continuing operations attributable to noncontrolling interests	0	0	0	0
Net income attributable to common shareholders	(132,581)	(144,901)	(265,436)	(249,796)
Other comprehensive income attributable to common shareholders	(69,355)	8,591	137,134	(10,349)
Comprehensive income attributable to common shareholders	(201,936)	(136,310)	(128,302)	(260,145)
Parent Company
Condensed Income Statements, Captions [Line Items]
Net revenues	0	0	0	0
Cost of goods sold	0	0	0	0
Gross profit	0	0	0	0
Selling, general and administrative expenses	8,663	11,025	20,115	21,803
Research and development expenses	0	0	0	0
Restructuring and impairment charges	0	0	0	0
Income from continuing operations before interest, extinguishment of debt and taxes	(8,663)	(11,025)	(20,115)	(21,803)
Interest, net	33,358	35,155	67,718	68,881
Loss on extinguishment of debt, net	10,454		10,454
Income from continuing operations before taxes	(52,475)	(46,180)	(98,287)	(90,684)
(Benefit) taxes on income from continuing operations	(17,941)	(15,710)	(33,234)	(31,130)
Equity in net income of consolidated subsidiaries	79,246	78,802	148,784	142,926
Income from continuing operations	44,712	48,332	83,731	83,372
Operating loss from discontinued operations	(145)	(1,594)	(648)	(1,619)
Taxes on loss from discontinued operations	4	(514)	168	(457)
Loss from discontinued operations	(149)	(1,080)	(816)	(1,162)
Net income	44,563	47,252	82,915	82,210
Less: Income from continuing operations attributable to noncontrolling interests	0	0	0	0
Net income attributable to common shareholders	44,563	47,252	82,915	82,210
Other comprehensive income attributable to common shareholders	20,986	1,862	(60,215)	6,607
Comprehensive income attributable to common shareholders	65,549	49,114	22,700	88,817
Guarantor Subsidiaries
Condensed Income Statements, Captions [Line Items]
Net revenues	269,703	290,280	533,864	552,705
Cost of goods sold	158,718	176,028	317,044	328,396
Gross profit	110,985	114,252	216,820	224,309
Selling, general and administrative expenses	82,844	76,575	167,112	157,970
Research and development expenses	4,894	12,885	16,021	24,895
Restructuring and impairment charges	591	8,679	4,330	8,491
Income from continuing operations before interest, extinguishment of debt and taxes	22,656	16,113	29,357	32,953
Interest, net	(18,565)	(20,740)	(37,134)	(40,647)
Loss on extinguishment of debt, net	0		0
Income from continuing operations before taxes	41,221	36,853	66,491	73,600
(Benefit) taxes on income from continuing operations	14,917	13,535	25,909	30,753
Equity in net income of consolidated subsidiaries	51,964	57,250	111,654	100,358
Income from continuing operations	78,268	80,568	152,236	143,205
Operating loss from discontinued operations	0	0	0	0
Taxes on loss from discontinued operations	0	0	0	0
Loss from discontinued operations	0	0	0	0
Net income	78,268	80,568	152,236	143,205
Less: Income from continuing operations attributable to noncontrolling interests	0	0	0	0
Net income attributable to common shareholders	78,268	80,568	152,236	143,205
Other comprehensive income attributable to common shareholders	45,015	(2,607)	(61,746)	4,621
Comprehensive income attributable to common shareholders	123,283	77,961	90,490	147,826
Non-Guarantor Subsidiaries
Condensed Income Statements, Captions [Line Items]
Net revenues	276,258	317,651	535,159	566,088
Cost of goods sold	152,355	177,009	289,973	314,882
Gross profit	123,903	140,642	245,186	251,206
Selling, general and administrative expenses	50,964	59,135	94,781	107,056
Research and development expenses	8,549	1,985	10,306	4,037
Restructuring and impairment charges	(11)	(1,056)	698	6,912
Income from continuing operations before interest, extinguishment of debt and taxes	64,401	80,578	139,401	133,201
Interest, net	1,260	1,501	2,472	2,899
Loss on extinguishment of debt, net	0		0
Income from continuing operations before taxes	63,141	79,077	136,929	130,302
(Benefit) taxes on income from continuing operations	8,463	14,344	23,207	23,176
Equity in net income of consolidated subsidiaries	122	98	219	192
Income from continuing operations	54,800	64,831	113,941	107,318
Operating loss from discontinued operations	0	0	4	0
Taxes on loss from discontinued operations	41	45	81	88
Loss from discontinued operations	(41)	(45)	(77)	(88)
Net income	54,759	64,786	113,864	107,230
Less: Income from continuing operations attributable to noncontrolling interests	446	453	664	639
Net income attributable to common shareholders	54,313	64,333	113,200	106,591
Other comprehensive income attributable to common shareholders	24,340	(5,984)	(75,388)	5,728
Comprehensive income attributable to common shareholders	$ 78,653	$ 58,349	$ 37,812	$ 112,319