Consolidated Statements of Equity - USD ($) $ in Millions	Total	Equity Incentive Plan	Cumulative Effect, Period of Adoption, Adjustment	Common Shares	Common Shares Equity Incentive Plan	Additional Paid-in-Capital	Additional Paid-in-Capital Equity Incentive Plan	Retained Earnings	Retained Earnings Cumulative Effect, Period of Adoption, Adjustment	Accumulated Other Comprehensive Loss
Beginning Balance (in shares) at Dec. 29, 2018				136,195,000
Beginning Balance at Dec. 29, 2018	$ 1,170.4		$ 10.5	$ 899.4		$ 73.9		$ 298.8	$ 10.5	$ (101.7)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net (loss) income	(15.3)							(15.3)
Other comprehensive income (loss), net of tax	14.1									14.1
Common shares dividends ($0.06 per common share)	(16.3)							(16.3)
Share-based compensation	6.8					6.8
Common shares repurchased and canceled (in shares)				(2,211,000)
Common shares repurchased and canceled	(31.0)			$ (16.4)				(14.6)
Common shares issued - Equity Incentive Plan (in shares)					605,000
Common shares issued - Equity Incentive Plan		$ 0.0			$ 6.3		$ (6.3)
Common shares issued - Dividend Reinvestment Plan (in shares)				3,000
Common shares issued - Dividend Reinvestment Plan	0.0
Common shares issued - Employee Stock Purchase Plan (in shares)				46,000
Common shares issued - Employee Stock Purchase Plan	0.7			$ 0.7
Ending Balance (in shares) at Jun. 29, 2019				134,638,000
Ending Balance at Jun. 29, 2019	1,139.9			$ 890.0		74.4		263.1		(87.6)
Beginning Balance (in shares) at Mar. 30, 2019				135,966,000
Beginning Balance at Mar. 30, 2019	1,151.0			$ 899.0		71.3		277.3		(96.6)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net (loss) income	4.4							4.4
Other comprehensive income (loss), net of tax	9.0									9.0
Common shares dividends ($0.06 per common share)	(8.1)							(8.1)
Share-based compensation	3.3					3.3
Common shares repurchased and canceled (in shares)				(1,441,000)
Common shares repurchased and canceled	(20.0)			$ (9.5)				(10.5)
Common shares issued - Equity Incentive Plan (in shares)					86,000
Common shares issued - Equity Incentive Plan		0.0			$ 0.2		(0.2)
Common shares issued - Dividend Reinvestment Plan (in shares)				3,000
Common shares issued - Dividend Reinvestment Plan	0.0
Common shares issued - Employee Stock Purchase Plan (in shares)				24,000
Common shares issued - Employee Stock Purchase Plan	0.3			$ 0.3
Ending Balance (in shares) at Jun. 29, 2019				134,638,000
Ending Balance at Jun. 29, 2019	$ 1,139.9			$ 890.0		74.4		263.1		(87.6)
Beginning Balance (in shares) at Dec. 28, 2019	134,803,211			134,803,000
Beginning Balance at Dec. 28, 2019	$ 1,166.2		(3.6)	$ 892.3		77.4		265.0	(3.6)	(68.5)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net (loss) income	(132.5)							(132.5)
Other comprehensive income (loss), net of tax	(21.5)									(21.5)
Common shares dividends ($0.06 per common share)	(19.5)							(19.5)
Share-based compensation	7.3					7.3
Common shares issued in connection with business combination and assumed vested awards, net of equity issuance costs of $1.1 million (in shares)				26,497,000
Common shares issued in connection with business combination and assumed vested awards, net of equity issuance costs of $1.1 million	379.4			$ 376.5		2.9
Common shares repurchased and canceled (in shares)				(2,796,000)
Common shares repurchased and canceled	(32.2)			$ (22.5)				(9.7)
Common shares issued - Equity Incentive Plan (in shares)					1,452,000
Common shares issued - Equity Incentive Plan		4.1			$ 16.3		(12.2)
Common shares issued - Dividend Reinvestment Plan (in shares)				1,000
Common shares issued - Dividend Reinvestment Plan	0.0
Common shares issued - Employee Stock Purchase Plan (in shares)				62,000
Common shares issued - Employee Stock Purchase Plan	$ 0.5			$ 0.7		(0.2)
Ending Balance (in shares) at Jun. 27, 2020	160,019,274			160,019,000
Ending Balance at Jun. 27, 2020	$ 1,348.2			$ 1,263.3		75.2		99.7		(90.0)
Beginning Balance (in shares) at Mar. 28, 2020				159,826,000
Beginning Balance at Mar. 28, 2020	1,480.7		$ 0.7	$ 1,262.7		71.5		244.9	$ 0.7	(98.4)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net (loss) income	(136.0)							(136.0)
Other comprehensive income (loss), net of tax	8.4									8.4
Common shares dividends ($0.06 per common share)	(9.9)							(9.9)
Share-based compensation	4.2					4.2
Common shares repurchased and canceled (in shares)				(20,000)
Common shares repurchased and canceled	(0.3)			$ (0.3)
Common shares issued - Equity Incentive Plan (in shares)					175,000
Common shares issued - Equity Incentive Plan		$ 0.2			$ 0.6		$ (0.4)
Common shares issued - Dividend Reinvestment Plan (in shares)				1,000
Common shares issued - Dividend Reinvestment Plan	0.0
Common shares issued - Employee Stock Purchase Plan (in shares)				37,000
Common shares issued - Employee Stock Purchase Plan	$ 0.2			$ 0.3		(0.1)
Ending Balance (in shares) at Jun. 27, 2020	160,019,274			160,019,000
Ending Balance at Jun. 27, 2020	$ 1,348.2			$ 1,263.3		$ 75.2		$ 99.7		$ (90.0)