Pension and Other Postretirement Benefits (Details) - USD ($) $ in Millions		3 Months Ended		9 Months Ended
	Aug. 10, 2016	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]
Total net pension cost and other postretirement benefit cost				$ 13.0	$ 23.8
Defined Benefit Plan, Plan Amendment [Abstract]
Net changes in pension and other postretirement plan assets and benefit obligations recognized in other comprehensive income, net of income taxes		$ 19.2	$ 0.0	19.2	0.0
Contribution to pension and other postemployment benefit plans				22.7
Future contributions to pension and other postemployment benefit plans				8.2
Defined Benefit Pension [Member]
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]
Service cost		4.6	4.3	12.2	12.7
Interest cost		6.7	8.0	19.7	23.8
Expected return on plan assets		(9.9)	(10.6)	(29.7)	(31.5)
Amortization of net loss		5.6	6.4	15.8	19.1
Amortization of prior service credit		(1.2)	(1.1)	(3.7)	(3.4)
Total net pension cost and other postretirement benefit cost		5.8	7.0	14.3	20.7
Other Postretirement Benefit [Member]
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]
Service cost		0.0	0.3	0.2	1.0
Interest cost		0.4	0.7	1.4	2.1
Amortization of net loss		0.2	0.0	0.2	0.0
Amortization of prior service credit		(2.9)	0.0	(3.1)	0.0
Total net pension cost and other postretirement benefit cost		$ (2.3)	$ 1.0	$ (1.3)	$ 3.1
Defined Benefit Plan, Plan Amendment [Abstract]
Decrease in postretirement benefits plan liability	$ (29.5)
Net changes in pension and other postretirement plan assets and benefit obligations recognized in other comprehensive income, net of income taxes	19.2
Increase in deferred tax liability	10.3
Other liabilities [Member] | Other Postretirement Benefit [Member]
Defined Benefit Plan, Plan Amendment [Abstract]
Plan change benefit	(39.9)
Remeasurement loss	5.2
Actuarial loss	5.2
Accumulated other comprehensive income (loss) [Member] | Other Postretirement Benefit [Member]
Defined Benefit Plan, Plan Amendment [Abstract]
Plan change benefit	25.9
Remeasurement loss	(3.4)
Actuarial loss	(3.3)
Deferred tax liability [Member] | Other Postretirement Benefit [Member]
Defined Benefit Plan, Plan Amendment [Abstract]
Plan change benefit	14.0
Remeasurement loss	(1.8)
Actuarial loss	$ (1.9)