Pension Plans and Other Postretirement Benefits - Defined Benefit Plan Estimated Future Benefit Payments (Detail) $ in Thousands	Dec. 31, 2019 USD ($)
Pension Benefits [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
2020	$ 100,800
2021	104,385
2022	107,368
2023	111,990
2024	115,962
2025 through 2029	619,663
Other Postretirement Benefits [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
2020	6,622
2021	4,036
2022	3,972
2023	3,904
2024	3,829
2025 through 2029	$ 17,919

Pension plans, postretirement and other employee benefits.

No definition available.

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-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

+ Details

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- Definition

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

+ References

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- Definition

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

+ References

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- Definition

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

+ References

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- Definition

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

+ References

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- Definition

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

+ References

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