Defined Contribution and Defined Benefit Retirement - Schedule of Defined Benefit Plan Expected Future Payments (Detail) - Defined Benefit Pension Plans $ in Millions	Dec. 31, 2020 USD ($)
Pension Plans Postretirement And Other Employee Benefits [Line Items]
2021	$ 27.5
2022	28.9
2023	28.7
2024	30.6
2025	30.6
Next 5 years	$ 177.6

Amount of benefit for defined benefit plan expected to be paid in five fiscal years after fifth fiscal year following current fiscal year.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

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Amount of benefit for defined benefit plan expected to be paid in next fiscal year following current fiscal year.

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Amount of benefit for defined benefit plan expected to be paid in fifth fiscal year following current fiscal year.

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Amount of benefit for defined benefit plan expected to be paid in fourth fiscal year following current fiscal year.

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Amount of benefit for defined benefit plan expected to be paid in third fiscal year following current fiscal year.

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Amount of benefit for defined benefit plan expected to be paid in second fiscal year following current fiscal year.

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- Definition

Pension plans postretirement and other employee benefits.

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