Condensed consolidating guarantor financial information Condensed consolidating statements of income and comprehensive income (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 29, 2015	Mar. 30, 2014
Condensed Income Statements, Captions [Line Items]
Net revenues	$ 429,430	$ 438,546
Cost of goods sold	206,793	217,387
Gross profit	222,637	221,159
Selling, general and administrative expenses	139,697	140,297
Research and development expenses	12,884	14,062
Restructuring and impairment charges	4,448	7,780
Income from continuing operations before interest and taxes	65,608	59,020
Interest expense	17,172	15,404
Interest income	(169)	(187)
Income from continuing operations before taxes	48,605	43,803
Taxes (benefit) on income from continuing operations	9,332	8,534
Equity in net income of consolidated subsidiaries	0	0
Income from continuing operations	39,273	35,269
Operating (loss) income from discontinued operations	(499)	(25)
Taxes on loss from discontinued operations	204	100
Loss from discontinued operations	(703)	(125)
Net income	38,570	35,144
Less: Income from continuing operations attributable to noncontrolling interests	218	186
Net income attributable to common shareholders	38,352	34,958
Other comprehensive loss attributable to common shareholders	(81,201)	4,745
Comprehensive (loss) income attributable to common shareholders	(42,849)	39,703
Consolidation, Eliminations
Condensed Income Statements, Captions [Line Items]
Net revenues	(93,632)	(72,316)
Cost of goods sold	(89,151)	(72,854)
Gross profit	(4,481)	538
Selling, general and administrative expenses	160	203
Research and development expenses	0	0
Restructuring and impairment charges	0	0
Income from continuing operations before interest and taxes	(4,641)	335
Interest expense	0
Interest income	0	0
Income from continuing operations before taxes	(4,641)	335
Taxes (benefit) on income from continuing operations	2,829	(2,096)
Equity in net income of consolidated subsidiaries	(132,868)	(107,326)
Income from continuing operations	(140,338)	(104,895)
Operating (loss) income from discontinued operations	0	0
Taxes on loss from discontinued operations	0	0
Loss from discontinued operations	0	0
Net income	(140,338)	(104,895)
Less: Income from continuing operations attributable to noncontrolling interests	0	0
Net income attributable to common shareholders	(140,338)	(104,895)
Other comprehensive loss attributable to common shareholders	183,051	(15,751)
Comprehensive (loss) income attributable to common shareholders	42,713	(120,646)
Parent Company
Condensed Income Statements, Captions [Line Items]
Net revenues	0	0
Cost of goods sold	0	0
Gross profit	0	0
Selling, general and administrative expenses	11,452	10,778
Research and development expenses	0	0
Restructuring and impairment charges	0	0
Income from continuing operations before interest and taxes	(11,452)	(10,778)
Interest expense	34,360	33,726
Interest income	0	0
Income from continuing operations before taxes	(45,812)	(44,504)
Taxes (benefit) on income from continuing operations	(15,293)	(15,420)
Equity in net income of consolidated subsidiaries	69,538	64,124
Income from continuing operations	39,019	35,040
Operating (loss) income from discontinued operations	(503)	(25)
Taxes on loss from discontinued operations	164	57
Loss from discontinued operations	(667)	(82)
Net income	38,352	34,958
Less: Income from continuing operations attributable to noncontrolling interests	0	0
Net income attributable to common shareholders	38,352	34,958
Other comprehensive loss attributable to common shareholders	(81,201)	4,745
Comprehensive (loss) income attributable to common shareholders	(42,849)	39,703
Guarantor Subsidiaries
Condensed Income Statements, Captions [Line Items]
Net revenues	264,161	262,425
Cost of goods sold	158,326	152,368
Gross profit	105,835	110,057
Selling, general and administrative expenses	84,268	81,395
Research and development expenses	11,127	12,010
Restructuring and impairment charges	3,739	(188)
Income from continuing operations before interest and taxes	6,701	16,840
Interest expense	(18,569)	(19,907)
Interest income	0	0
Income from continuing operations before taxes	25,270	36,747
Taxes (benefit) on income from continuing operations	10,992	17,218
Equity in net income of consolidated subsidiaries	63,233	43,108
Income from continuing operations	77,511	62,637
Operating (loss) income from discontinued operations	0	0
Taxes on loss from discontinued operations	0	0
Loss from discontinued operations	0	0
Net income	77,511	62,637
Less: Income from continuing operations attributable to noncontrolling interests	0	0
Net income attributable to common shareholders	77,511	62,637
Other comprehensive loss attributable to common shareholders	(106,761)	7,228
Comprehensive (loss) income attributable to common shareholders	(29,250)	69,865
Non-Guarantor Subsidiaries
Condensed Income Statements, Captions [Line Items]
Net revenues	258,901	248,437
Cost of goods sold	137,618	137,873
Gross profit	121,283	110,564
Selling, general and administrative expenses	43,817	47,921
Research and development expenses	1,757	2,052
Restructuring and impairment charges	709	7,968
Income from continuing operations before interest and taxes	75,000	52,623
Interest expense	1,381	1,585
Interest income	(169)	(187)
Income from continuing operations before taxes	73,788	51,225
Taxes (benefit) on income from continuing operations	10,804	8,832
Equity in net income of consolidated subsidiaries	97	94
Income from continuing operations	63,081	42,487
Operating (loss) income from discontinued operations	4	0
Taxes on loss from discontinued operations	40	43
Loss from discontinued operations	(36)	(43)
Net income	63,045	42,444
Less: Income from continuing operations attributable to noncontrolling interests	218	186
Net income attributable to common shareholders	62,827	42,258
Other comprehensive loss attributable to common shareholders	(76,290)	8,523
Comprehensive (loss) income attributable to common shareholders	$ (13,463)	$ 50,781