Accumulated Other Comprehensive Income (Schedule of Accumulated Other Comprehensive Income) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2017	Mar. 25, 2016
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	$ (72.5)	$ (65.3)
Other comprehensive (loss) income before reclassifications	30.7	(3.6)
Amounts reclassified from accumulated other comprehensive income	31.9	3.8
Net current period other comprehensive (loss) income	62.6	0.2
Ending balance	(9.9)	(65.1)
Accumulated Currency Translation Adjustment
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	(19.5)	(7.9)
Other comprehensive (loss) income before reclassifications	7.1	8.8
Amounts reclassified from accumulated other comprehensive income	(4.7)	0.0
Net current period other comprehensive (loss) income	2.4	8.8
Ending balance	(17.1)	0.9
Accumulated Unrecognized Gain (Loss) on Derivatives
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	(5.7)	(6.3)
Other comprehensive (loss) income before reclassifications	0.0	0.0
Amounts reclassified from accumulated other comprehensive income	0.2	0.2
Net current period other comprehensive (loss) income	0.2	0.2
Ending balance	(5.5)	(6.1)
Accumulated Unrecognized Gain (Loss) on Benefit Plans
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	(47.3)	(51.1)
Other comprehensive (loss) income before reclassifications	10.2	(12.4)
Amounts reclassified from accumulated other comprehensive income	36.4	3.6
Net current period other comprehensive (loss) income	46.6	(8.8)
Ending balance	(0.7)	(59.9)
Accumulated Unrecognized Gain on Equity Securities
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	0.0	0.0
Other comprehensive (loss) income before reclassifications	13.4	0.0
Amounts reclassified from accumulated other comprehensive income	0.0	0.0
Net current period other comprehensive (loss) income	13.4	0.0
Ending balance	$ 13.4	$ 0.0