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Shareholders' Equity (Share Repurchases) (Details) - USD ($) $ / shares in Units, shares in Thousands	1 Months Ended		12 Months Ended
	Nov. 30, 2018	Nov. 30, 2016	Dec. 25, 2019	Dec. 26, 2018	Dec. 27, 2017	Dec. 28, 2016
Equity, Class of Treasury Stock [Line Items]
Purchase of treasury stock			$ 96,202,000	$ 61,189,000	$ 82,858,000
Purchase of treasury stock (in shares)				3,900	6,800
Stock repurchased during period (in shares)			5,300
Stock repurchased during period			$ 103,000,000.0
Share Repurchase Program 2019
Equity, Class of Treasury Stock [Line Items]
Share repurchase, authorized amount			250,000,000
Share Repurchase Program 2017
Equity, Class of Treasury Stock [Line Items]
Share repurchase, authorized amount					$ 200,000,000
Share Repurchase Program 2016
Equity, Class of Treasury Stock [Line Items]
Share repurchase, authorized amount						$ 100,000,000
Accelerated Share Repurchase 2016
Equity, Class of Treasury Stock [Line Items]
Share repurchase, authorized amount		$ 25,000,000
Purchase of equity forward contract		$ 25,000,000
Purchase of treasury stock					$ 6,900,000
Purchase of treasury stock (in shares)		1,500			500
Volume-weighted average price (in usd per share)					$ 12.36
Accelerated Share Repurchase 2018
Equity, Class of Treasury Stock [Line Items]
Share repurchase, authorized amount	$ 25,000,000
Purchase of equity forward contract		$ 25,000,000
Purchase of treasury stock			$ 6,800,000
Purchase of treasury stock (in shares)	1,100		400
Volume-weighted average price (in usd per share)			$ 17.04
Share Repurchase Program 2017 And 2019
Equity, Class of Treasury Stock [Line Items]
Remaining shares to be repurchased amount			$ 282,200,000
Treasury Stock
Equity, Class of Treasury Stock [Line Items]
Purchase of treasury stock			$ 96,202,000	$ 61,189,000	$ 82,858,000
Purchase of treasury stock (in shares)			4,879	3,901	6,840
Treasury Stock | Accelerated Share Repurchase 2016
Equity, Class of Treasury Stock [Line Items]
Purchase of treasury stock		$ 18,100,000
Purchase of treasury stock (in shares)					554
Treasury Stock | Accelerated Share Repurchase 2018
Equity, Class of Treasury Stock [Line Items]
Purchase of treasury stock	$ 18,200,000
Purchase of treasury stock (in shares)			389
Additional Paid-in Capital | Accelerated Share Repurchase 2016
Equity, Class of Treasury Stock [Line Items]
Remaining shares to be repurchased amount						$ 6,900,000
Additional Paid-in Capital | Accelerated Share Repurchase 2018
Equity, Class of Treasury Stock [Line Items]
Remaining shares to be repurchased amount				$ 6,800,000

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