Income Taxes (Details) - USD ($) $ in Millions		3 Months Ended		9 Months Ended		12 Months Ended
	Aug. 15, 2017	Sep. 30, 2017	Oct. 01, 2016	Sep. 30, 2017	Oct. 01, 2016	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009	Dec. 31, 2016
Effective income tax rate reconciliation, percent		65.50%	16.40%	68.70%	17.20%
Unrecognized tax benefits, including income tax penalties and interest accrued		$ 454.9		$ 454.9						$ 398.0
Unrecognized tax benefits liability, interest and penalties accrued		$ 79.0		$ 79.0						$ 63.5
Income tax examination, penalties and interest expense	$ 163.6					$ 24.7	$ 40.2	$ 61.5	$ 37.2