Postretirement Benefit Plans - Changes in Fair Value of Plan Assets of Pension and Other Employee-Related Defined Benefit Plans (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Change in plan assets
Plan assets - January 1	$ 283.4	$ 278.0
Actual return on plan assets	(7.9)	22.5
Employer contributions	18.6	12.6
Benefits and expenses paid	(29.1)	(28.1)
Acquired	23.1	0.0
Settlement	(1.1)	(1.6)
Defined Benefit Plan, Foreign Currency Exchange Rate Changes, Plan Assets	(0.1)	0.0
Plan assets - December 31	286.9	283.4
Funded status at end of year	(274.4)	(262.7)
U.S. Pension Plans [Member]
Change in plan assets
Plan assets - January 1	272.9	266.8
Actual return on plan assets	(8.0)	22.1
Employer contributions	8.6	0.9
Benefits and expenses paid	(18.5)	(16.9)
Acquired	23.1	0.0
Settlement	0.0	0.0
Defined Benefit Plan, Foreign Currency Exchange Rate Changes, Plan Assets	0.0	0.0
Plan assets - December 31	278.1	272.9
Funded status at end of year	(61.8)	(51.2)
International Pension Plan [Member]
Change in plan assets
Plan assets - January 1	1.0	2.0
Actual return on plan assets	0.0	0.1
Employer contributions	3.8	3.5
Benefits and expenses paid	(2.7)	(3.0)
Acquired	0.0	0.0
Settlement	(1.1)	(1.6)
Defined Benefit Plan, Foreign Currency Exchange Rate Changes, Plan Assets	(0.1)	0.0
Plan assets - December 31	0.9	1.0
Funded status at end of year	(77.1)	(86.5)
Other Postretirement Benefit Plan [Member]
Change in plan assets
Plan assets - January 1	9.5	9.2
Actual return on plan assets	0.1	0.3
Employer contributions	6.2	8.2
Benefits and expenses paid	(7.9)	(8.2)
Acquired	0.0	0.0
Settlement	0.0	0.0
Defined Benefit Plan, Foreign Currency Exchange Rate Changes, Plan Assets	0.0	0.0
Plan assets - December 31	7.9	9.5
Funded status at end of year	$ (135.5)	$ (125.0)