Retirement Plans and Other Postretirement Benefits - Estimated Future Benefit Payments (Details) $ in Thousands	Dec. 31, 2020 USD ($)
Pension Benefits
Estimated Future Benefit Payments
2021	$ 210,119
2022	209,593
2023	215,527
2024	220,241
2025	220,787
Years 2026-2030	1,116,848
Other Benefits
Estimated Future Benefit Payments
2021	31,204
2022	31,731
2023	32,196
2024	31,914
2025	31,484
Years 2026-2030	$ 153,536

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- Definition

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

+ References

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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