Goodwill and other intangible assets, net - Components of intangible assets (Details) - USD ($) $ in Thousands	Apr. 01, 2018	Dec. 31, 2017
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	$ 3,016,337	$ 2,964,632
Accumulated Amortization	(625,782)	(580,884)
In-process research and development
Finite-Lived Intangible Assets [Line Items]
In-process research and development	31,698	34,672
Customer relationships
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets	1,044,509	1,023,837
Accumulated Amortization	(295,480)	(281,263)
Intellectual property
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets	1,312,598	1,287,487
Accumulated Amortization	(282,907)	(258,580)
Distribution rights
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets	23,922	23,697
Accumulated Amortization	(17,490)	(16,996)
Trade names
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets	578,646	571,510
Accumulated Amortization	(25,990)	(22,069)
Non-compete agreements
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets	24,964	23,429
Accumulated Amortization	$ (3,915)	$ (1,976)