Amount of contributions received and expected to be received by defined benefit plan from employer in current fiscal year.

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Amount of contribution expected to be received by defined benefit plan from employer in remainder of current fiscal year. Excludes contribution previously paid by employer in current fiscal year.

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Amount of cash outflow for other postretirement benefit. Includes, but is not limited to, employer contribution to fund plan asset and payment to retiree. Excludes pension benefit.

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Pension and Postretirement Benefits - Additional Information (Detail) - USD ($) $ in Millions	9 Months Ended		12 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Cash contributions, pension plans	$ 340.2	$ 78.8	$ 103.9
Cash contributions, postretirement benefits	344.5	82.3
Pension Plans
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Additional cash contributions expected to make for remainder of current fiscal year	485.6
Estimated cash contributions by the company for current fiscal year	825.8
Pension Plans \| U.S. Plans
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Estimated cash contributions by the company for current fiscal year	793.1
Pension Plans \| International Plans
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Estimated cash contributions by the company for current fiscal year	32.7
Postretirement Benefit Plans
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Estimated cash contributions by the company for current fiscal year	6.0
Cash contributions, postretirement benefits	$ 4.3	$ 3.5	$ 5.5