Earnings (Loss) Per Share And Shareholder's Equity - Schedule of Dividends (Details) - USD ($) $ / shares in Units, $ in Millions	6 Months Ended		12 Months Ended
	Dec. 31, 2015	Dec. 27, 2014	Dec. 31, 2017	Dec. 31, 2016	Jun. 27, 2015
Earnings Per Share [Abstract]
Dividends paid (in millions)	$ 36.3		$ 91.1	$ 83.2	$ 64.8
Dividends paid (per share)	$ 0.25	$ 0.21	$ 0.64	$ 0.58	$ 0.4600