Pension Plans for which ABO exceeds Fair Value of Plan Assets (Detail) - Pension Plans, Defined Benefit - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
U.S. Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Projected Benefit Obligation (PBO)	$ 426.2	$ 400.1
Accumulated Benefit Obligation (ABO)	419.1	384.3
Fair value of plan assets	354.6	323.8
Non-U.S. Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Projected Benefit Obligation (PBO)	179.2	169.3
Accumulated Benefit Obligation (ABO)	142.7	127.2
Fair value of plan assets	$ 4.0	$ 3.8

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Amount of accumulated benefit obligation for defined benefit plan with accumulated benefit obligation in excess of plan assets.

+ References

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-Publisher FASB
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Amount of plan asset for defined benefit plan with accumulated benefit obligation in excess of plan assets.

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Amount of projected benefit obligation for defined benefit pension plan with accumulated benefit obligation in excess of plan assets.

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