Income Taxes - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Taxes [Line Items]
Federal statutory corporate income tax rate		21.00%	21.00%	35.00%
Tax benefit for the provisional impact of 2017 Tax Act				$ 258.1
Income tax benefit from net operating loss (NOL) carryforwards utilized			$ 5.8
Foreign pretax earnings		$ 15.1	5.7	10.6
Increased net earnings		$ 15.2		$ 15.5
Increased net earnings, per share		$ 0.24		$ 0.25
Tax deduction, percentage				9.00%
Operating loss carryforwards, expiration dates		2039
Deferred tax assets recognized		$ 10.5	11.0
Deferred tax asset, valuation allowance		$ 9.0	8.6
Percentage of impact of expensing of capital expenditures for tax purposes and change in tax status		100.00%
Unrecognized tax benefits, excluding interest and correlative effects		$ 1.7	0.6
Tax refund				$ 3.9
Open tax years		2011 2012 2013 2014 2015 2016 2017 2018 2019
Maximum | Scenario, Forecast
Income Taxes [Line Items]
Decrease in unrecognized tax benefits, excluding interest and correlative effects	$ 17.1
Federal Tax Authority
Income Taxes [Line Items]
Operating loss carryforwards, amount		$ 4.1	3.2
State Tax Authority
Income Taxes [Line Items]
Operating loss carryforwards, amount		161.0	168.1
Domestic State Tax Authority
Income Taxes [Line Items]
Domestic and foreign tax credits, amount		$ 1.1	1.0
Domestic tax credits, expiration year		2039
Deferred tax assets recognized		$ 0.9	0.8
Tax Year 2017
Income Taxes [Line Items]
Income tax expense for transition tax on undistributed foreign earnings			1.1
Income tax expense, write off of deferred tax assets			1.5
Income tax benefit of pension funding, inventory and insurance prepayments			$ 21.5
Earliest Tax Year
Income Taxes [Line Items]
Expiration date of statute of limitations		2010
Latest Tax Year
Income Taxes [Line Items]
Expiration date of statute of limitations		2013