Condensed Consolidated Statement of Changes in Shareholders' Equity Statement - USD ($) $ in Millions	Total	Ordinary Shares	Treasury Shares	Additional Paid-In Capital	Retained Earnings (Deficit)	Accumulated Other Comprehensive Loss
Beginning balance, ordinary shares (in shares) at Dec. 29, 2017		92,200,000
Beginning balance, treasury shares (in shares) at Dec. 29, 2017			5,900,000
Beginning balance at Dec. 29, 2017	$ 6,522.0	$ 18.4	$ (1,564.7)	$ 5,492.6	$ 2,588.6	$ (12.9)
Impact of accounting standard adoptions, net of tax	1.1				2.6	(1.5)
Net income (loss)	(18.0)				(18.0)
Currency translation adjustments	(2.3)					(2.3)
Change in derivatives, net of tax	0.4					0.4
Change in benefit plans, net of tax	(0.5)					(0.5)
Vesting of restricted shares (in shares)		300,000	0
Vesting of restricted shares (in usd)	(1.3)	$ 0.1	$ (1.4)	0.0
Share-based compensation	4.6			4.6
Stock Issued During Period, Shares, Treasury Stock Reissued			0
Reissuance of treasury shares	0.5		$ 0.8		(0.3)
Repurchase of shares (in shares)			2,900,000
Repurchase of shares (in usd)	(45.2)		$ 45.2
Ending balance, ordinary shares (in shares) at Mar. 30, 2018		92,500,000
Ending balance, treasury shares (in shares) at Mar. 30, 2018			8,800,000
Ending balance at Mar. 30, 2018	$ 6,461.3	$ 18.5	$ (1,610.5)	5,497.2	2,572.9	(16.8)
Beginning balance, ordinary shares (in shares) at Dec. 28, 2018	92,705,747	92,700,000
Beginning balance, treasury shares (in shares) at Dec. 28, 2018	9,381,870		9,400,000
Beginning balance at Dec. 28, 2018	$ 2,887.3	$ 18.5	$ (1,617.4)	5,528.2	(1,017.7)	(24.3)
Impact of accounting standard adoptions, net of tax	0.0				(0.5)	0.5
Net income (loss)	154.9				154.9
Currency translation adjustments	1.4					1.4
Change in derivatives, net of tax	0.2					0.2
Change in benefit plans, net of tax	(0.3)					(0.3)
Stock Issued During Period, Value, Stock Options Exercised	0.3			0.3
Vesting of restricted shares (in shares)		200,000	0
Vesting of restricted shares (in usd)	(0.4)	$ 0.1	$ (0.5)	0.0
Share-based compensation	10.0			10.0
Stock Issued During Period, Shares, Treasury Stock Reissued			0
Reissuance of treasury shares	$ 0.5		$ 0.9		(0.4)
Ending balance, ordinary shares (in shares) at Mar. 29, 2019	92,912,986	92,900,000
Ending balance, treasury shares (in shares) at Mar. 29, 2019	9,376,157		9,400,000
Ending balance at Mar. 29, 2019	$ 3,053.9	$ 18.6	$ (1,617.0)	$ 5,538.5	$ (863.7)	$ (22.5)