Employee Benefit and Retirement Plans - Composition of International Pension Plan Assets (Detail) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
International [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, fair value of plan assets	$ 621.2	$ 565.3
International [Member] | Fair Value [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, fair value of plan assets	560.9	431.5
International [Member] | Portion at Other than Fair Value Measurement [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, fair value of plan assets	60.3	133.8
International [Member] | Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, fair value of plan assets	52.9	71.0
International [Member] | Equity Securities [Member] | Fair Value [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, fair value of plan assets	38.8	26.2
International [Member] | Equity Securities [Member] | Portion at Other than Fair Value Measurement [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, fair value of plan assets	14.1	44.8
International [Member] | Fixed Income Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, fair value of plan assets	273.2	215.6
International [Member] | Fixed Income Securities [Member] | Fair Value [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, fair value of plan assets	258.8	169.3
International [Member] | Fixed Income Securities [Member] | Portion at Other than Fair Value Measurement [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, fair value of plan assets	14.4	46.3
International [Member] | Cash and Other Investments [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, fair value of plan assets	295.1	278.7
International [Member] | Cash and Other Investments [Member] | Fair Value [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, fair value of plan assets	263.3	236.0
International [Member] | Cash and Other Investments [Member] | Portion at Other than Fair Value Measurement [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, fair value of plan assets	31.8	42.7
Level 1 [Member] | International [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, fair value of plan assets	304.3	194.9
Level 1 [Member] | International [Member] | Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, fair value of plan assets	38.8	26.2
Level 1 [Member] | International [Member] | Fixed Income Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, fair value of plan assets	258.8	164.0
Level 1 [Member] | International [Member] | Cash and Other Investments [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, fair value of plan assets	6.7	4.7
Level 2 [Member] | International [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, fair value of plan assets	242.9	217.8
Level 2 [Member] | International [Member] | Cash and Other Investments [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, fair value of plan assets	242.9	217.8
Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, fair value of plan assets	33.0	39.0	$ 26.9
Level 3 [Member] | International [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, fair value of plan assets	13.7	18.8
Level 3 [Member] | International [Member] | Fixed Income Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, fair value of plan assets		5.3
Level 3 [Member] | International [Member] | Cash and Other Investments [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, fair value of plan assets	$ 13.7	$ 13.5