Employee Benefit Plans (Details) In Millions, unless otherwise specified	3 Months Ended	12 Months Ended				12 Months Ended				12 Months Ended		12 Months Ended		12 Months Ended		12 Months Ended		12 Months Ended		12 Months Ended		12 Months Ended		0 Months Ended	3 Months Ended		12 Months Ended					12 Months Ended		12 Months Ended		12 Months Ended		12 Months Ended		12 Months Ended
	Mar. 29, 2014 USD ($) item	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($) item	Dec. 31, 2014 Pension plans	Dec. 31, 2013 Pension plans	Dec. 31, 2014 Domestic Pension Plans USD ($)	Dec. 31, 2013 Domestic Pension Plans USD ($)	Dec. 31, 2014 Domestic Pension Plans Fixed Income Common Trust Funds	Dec. 31, 2013 Domestic Pension Plans Fixed Income Common Trust Funds	Dec. 31, 2014 Domestic Pension Plans Commingled Global Fund Allocations	Dec. 31, 2013 Domestic Pension Plans Commingled Global Fund Allocations	Dec. 31, 2014 Domestic Pension Plans Corporate bonds	Dec. 31, 2013 Domestic Pension Plans Corporate bonds	Dec. 31, 2014 Domestic Pension Plans Global Equity Common Trust Funds	Dec. 31, 2013 Domestic Pension Plans Global Equity Common Trust Funds	Dec. 31, 2014 Domestic Pension Plans Global equities	Dec. 31, 2013 Domestic Pension Plans Global equities	Dec. 31, 2014 Domestic Pension Plans U.S. Government securities	Dec. 31, 2013 Domestic Pension Plans U.S. Government securities	Dec. 31, 2014 Domestic Pension Plans Short-term investments	Dec. 31, 2013 Domestic Pension Plans Short-term investments	Dec. 31, 2014 Domestic Pension Plans Other	Dec. 31, 2013 Domestic Pension Plans Other	Dec. 31, 2014 Foreign Pension Plans item	Dec. 31, 2014 Foreign Pension Plans USD ($)	Dec. 31, 2014 Foreign Pension Plans GBP (£)	Dec. 31, 2014 Foreign Pension Plans USD ($) item	Dec. 31, 2014 Foreign Pension Plans GBP (£)	Dec. 31, 2013 Foreign Pension Plans USD ($)	Dec. 31, 2014 Foreign Pension Plans Fixed Income Common Trust Funds	Dec. 31, 2013 Foreign Pension Plans Fixed Income Common Trust Funds	Dec. 31, 2014 Foreign Pension Plans Global Equity Common Trust Funds	Dec. 31, 2013 Foreign Pension Plans Global Equity Common Trust Funds	Dec. 31, 2014 Foreign Pension Plans Non-U.S. Government securities	Dec. 31, 2013 Foreign Pension Plans Non-U.S. Government securities	Dec. 31, 2014 Foreign Pension Plans Short-term investments	Dec. 31, 2013 Foreign Pension Plans Short-term investments	Dec. 31, 2014 Foreign Pension Plans Other	Dec. 31, 2013 Foreign Pension Plans Other	Dec. 31, 2014 Postretirement Plans USD ($)	Dec. 31, 2013 Postretirement Plans USD ($)
Employee benefit plans
Number of retirees assumed by third party for future pension payments			16,000																					900			900	900
Amount paid for obligations assumed by third party	$ 4.8		$ 663.7																						$ 123.3	£ 79.2	$ 123.3	£ 79.2
Obligations assumed by third party			609.0																						105.8	68.0
Settlement gain (loss) resulting from partial annuitization		4.8	4.8
Number of eligible former employees intended to be offered with voluntary single lump-sum payment option in lieu of a future pension benefit	7,100
Percentage of projected benefit obligation of the Plan settled as a result of lump-sum payments	38.00%
Projected benefit obligation of the Plan settled as a result of lump-sum payments	165.2
Settlement charge	4.6
Actuarial loss	(14.8)					(59.5)	49.8																				(55.3)		(9.6)											(14.2)	7.8
Settlement charges		$ 15.0				$ 160.4	$ 708.8																				$ 127.7
Number of shares of common stock held by defined benefit plans				0	0
Actual Allocations (as a percent)						100.00%	100.00%	53.00%	20.00%	12.00%	15.00%	12.00%	0.00%	11.00%	25.00%	4.00%	6.00%	4.00%	0.00%	3.00%	33.00%	1.00%	1.00%		100.00%	100.00%	100.00%	100.00%	100.00%	8.00%	40.00%	69.00%	43.00%	15.00%	14.00%	6.00%	2.00%	2.00%	1.00%
Mid-point of Target Allocation Range (as a percent)						100.00%		49.00%		18.00%		12.00%		10.00%		5.00%		4.00%		0.00%		2.00%					100.00%	100.00%		31.00%		44.00%		22.00%		1.00%		2.00%