Acquisitions - Narrative (Details) $ in Millions		3 Months Ended	9 Months Ended	12 Months Ended
	Apr. 01, 2019 USD ($) country	Sep. 27, 2019 USD ($)	Sep. 27, 2019 USD ($) business country	Dec. 31, 2018 USD ($)
Business Acquisition [Line Items]
Adjustments to preliminary purchase price allocations for acquisitions completed in 2018			$ 72.0
Acquisitions, ASP
Business Acquisition [Line Items]
Net cash consideration	$ 2,700.0		$ 2,700.0
Revenue attributable to acquisition				$ 800.0
Number of principal countries | country	20
Number of non-principal countries | country	39
Number of principal countries, acquired | country			20
Number of non-principal countries, acquired | country			3
Percent of preliminary valuation in principal countries		98.00%	98.00%
Percent of preliminary valuation in non-principal countries		2.00%	2.00%
Prepaid acquisition asset related to Non-Principal Countries		$ 64.6	$ 64.6
Revenue since date of acquisition		169.5	334.4
Operating loss since date of acquisition		26.6	90.5
Amortization of intangible assets, acquisition-related fair value adjustments, and transaction costs		64.8	166.6
Transaction-related costs		20.0	71.0
Other Acquisitions
Business Acquisition [Line Items]
Net cash consideration			683.6
Additional equity investments			4.1
Revenue attributable to acquisition				$ 149.0
Transaction-related costs		1.0	$ 4.0
Number of businesses acquired | business			3
Tax deductible goodwill		$ 17.0	$ 17.0