Condensed consolidating guarantor financial information Condensed consolidating statements of cash flows (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 28, 2015	Jun. 29, 2014
Net Cash Provided by (Used in) Operating Activities, Continuing Operations [Abstract]
Net cash (used in) provided by operating activities from continuing operations	$ 109,588	$ 120,161
Net Cash Provided by (Used in) Investing Activities [Abstract]
Expenditures for property, plant and equipment	(31,321)	(30,850)
Proceeds from sale of assets and investments	0	4,139
Payments for businesses and intangibles acquired, net of cash acquired	(37,559)	(28,535)
Investments in affiliates	0	(60)
Net cash used in investing activities from continuing operations	(68,880)	(55,306)
Cash Flows from Financing Activities of Continuing Operations:
Proceeds from new borrowings	288,100	250,000
Repayment of long-term borrowings	(250,981)	(480,000)
Debt extinguishment, issuance and amendment fees	(8,746)	(3,275)
Payments to noncontrolling interest shareholders	(832)	(1,094)
Net proceeds from share based compensation plans and the related tax impacts	4,843	2,391
Payments for contingent consideration	(3,989)	0
Dividends	(28,234)	(28,093)
Intercompany transactions	0	0
Intercompany dividends paid	0
Net cash provided by (used in) financing activities from continuing operations	161	(260,071)
Cash Flows from Discontinued Operations:
Net cash used in operating activities	(1,363)	(1,531)
Net cash used in discontinued operations	(1,363)	(1,531)
Effect of exchange rate changes on cash and cash equivalents	(17,732)	2,145
Net increase (decrease) in cash and cash equivalents	21,774	(194,602)
Cash and cash equivalents at the beginning of the period	303,236	431,984
Cash and cash equivalents at the end of the period	325,010	237,382
Consolidation, Eliminations
Net Cash Provided by (Used in) Operating Activities, Continuing Operations [Abstract]
Net cash (used in) provided by operating activities from continuing operations	(2,360)	(3,135)
Net Cash Provided by (Used in) Investing Activities [Abstract]
Expenditures for property, plant and equipment	0	0
Proceeds from sale of assets and investments		0
Payments for businesses and intangibles acquired, net of cash acquired	0	0
Investments in affiliates		0
Intercompany dividends received		0
Net cash used in investing activities from continuing operations	0	0
Cash Flows from Financing Activities of Continuing Operations:
Proceeds from new borrowings	0	0
Repayment of long-term borrowings	0	0
Debt extinguishment, issuance and amendment fees	0	0
Payments to noncontrolling interest shareholders	0
Net proceeds from share based compensation plans and the related tax impacts	0	0
Payments for contingent consideration	0
Dividends	0	0
Intercompany transactions	0	0
Intercompany dividends paid	2,360	3,135
Net cash provided by (used in) financing activities from continuing operations	2,360	3,135
Cash Flows from Discontinued Operations:
Net cash used in operating activities	0	0
Net cash used in discontinued operations	0	0
Effect of exchange rate changes on cash and cash equivalents	0	0
Net increase (decrease) in cash and cash equivalents	0	0
Cash and cash equivalents at the beginning of the period	0	0
Cash and cash equivalents at the end of the period	0	0
Parent Company
Net Cash Provided by (Used in) Operating Activities, Continuing Operations [Abstract]
Net cash (used in) provided by operating activities from continuing operations	(92,490)	(49,308)
Net Cash Provided by (Used in) Investing Activities [Abstract]
Expenditures for property, plant and equipment	(108)	(2,019)
Proceeds from sale of assets and investments		1,669
Payments for businesses and intangibles acquired, net of cash acquired	0	0
Investments in affiliates		(60)
Net cash used in investing activities from continuing operations	(108)	(410)
Cash Flows from Financing Activities of Continuing Operations:
Proceeds from new borrowings	288,100	250,000
Repayment of long-term borrowings	(250,981)	(480,000)
Debt extinguishment, issuance and amendment fees	(8,746)	(3,275)
Payments to noncontrolling interest shareholders	0	0
Net proceeds from share based compensation plans and the related tax impacts	4,843	2,391
Payments for contingent consideration	0
Dividends	(28,234)	(28,093)
Intercompany transactions	86,197	298,760
Intercompany dividends paid	0	0
Net cash provided by (used in) financing activities from continuing operations	91,179	39,783
Cash Flows from Discontinued Operations:
Net cash used in operating activities	(514)	(1,531)
Net cash used in discontinued operations	(514)	(1,531)
Effect of exchange rate changes on cash and cash equivalents	0	0
Net increase (decrease) in cash and cash equivalents	(1,933)	(11,466)
Cash and cash equivalents at the beginning of the period	27,996	42,749
Cash and cash equivalents at the end of the period	26,063	31,283
Guarantor Subsidiaries
Net Cash Provided by (Used in) Operating Activities, Continuing Operations [Abstract]
Net cash (used in) provided by operating activities from continuing operations	63,718	277,906
Net Cash Provided by (Used in) Investing Activities [Abstract]
Expenditures for property, plant and equipment	(17,339)	(14,080)
Proceeds from sale of assets and investments		2,470
Payments for businesses and intangibles acquired, net of cash acquired	(4,348)	0
Investments in affiliates		0
Net cash used in investing activities from continuing operations	(21,687)	(11,610)
Cash Flows from Financing Activities of Continuing Operations:
Proceeds from new borrowings	0	0
Repayment of long-term borrowings	0	0
Debt extinguishment, issuance and amendment fees	0	0
Payments to noncontrolling interest shareholders	0	0
Net proceeds from share based compensation plans and the related tax impacts	0	0
Payments for contingent consideration	(3,989)
Dividends	0	0
Intercompany transactions	(37,744)	(277,561)
Intercompany dividends paid	0	0
Net cash provided by (used in) financing activities from continuing operations	(41,733)	(277,561)
Cash Flows from Discontinued Operations:
Net cash used in operating activities	0	0
Net cash used in discontinued operations	0	0
Effect of exchange rate changes on cash and cash equivalents	0	0
Net increase (decrease) in cash and cash equivalents	298	(11,265)
Cash and cash equivalents at the beginning of the period	0	14,500
Cash and cash equivalents at the end of the period	298	3,235
Non-Guarantor Subsidiaries
Net Cash Provided by (Used in) Operating Activities, Continuing Operations [Abstract]
Net cash (used in) provided by operating activities from continuing operations	140,720	(105,302)
Net Cash Provided by (Used in) Investing Activities [Abstract]
Expenditures for property, plant and equipment	(13,874)	(14,751)
Proceeds from sale of assets and investments		0
Payments for businesses and intangibles acquired, net of cash acquired	(33,211)	(28,535)
Investments in affiliates		0
Intercompany dividends received		0
Net cash used in investing activities from continuing operations	(47,085)	(43,286)
Cash Flows from Financing Activities of Continuing Operations:
Proceeds from new borrowings	0	0
Repayment of long-term borrowings	0	0
Debt extinguishment, issuance and amendment fees	0	0
Payments to noncontrolling interest shareholders	(832)	(1,094)
Net proceeds from share based compensation plans and the related tax impacts	0	0
Payments for contingent consideration	0
Dividends	0	0
Intercompany transactions	(48,453)	(21,199)
Intercompany dividends paid	(2,360)	(3,135)
Net cash provided by (used in) financing activities from continuing operations	(51,645)	(25,428)
Cash Flows from Discontinued Operations:
Net cash used in operating activities	(849)	0
Net cash used in discontinued operations	(849)	0
Effect of exchange rate changes on cash and cash equivalents	(17,732)	2,145
Net increase (decrease) in cash and cash equivalents	23,409	(171,871)
Cash and cash equivalents at the beginning of the period	275,240	374,735
Cash and cash equivalents at the end of the period	$ 298,649	$ 202,864