Employee Benefit and Retirement Plans - Summary of Reconciliation of Change in Fair Value Measurement of Defined Benefit Plans' Consolidated Assets Using Significant Unobservable Inputs (Level 3) (Detail) - Level 3 - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets at beginning of year	$ 10.4	$ 14.9
Realized gains	0.0	0.0
Unrealized (losses) gains	0.2	0.1
Purchases, sales, settlements and other, net	1.5	4.6
Fair value of plan assets at end of year	$ 9.1	$ 10.4