Employee Benefit Plans and Other Postretirement Benefits - Schedule Of Expected Benefit Payments For Next Five Years And Thereafter (Details) $ in Thousands	Dec. 31, 2020 USD ($)
Pension Plan Assets
Defined Benefit Plan, Expected Future Benefit Payment [Abstract]
Expected benefit payments in 2021	$ 99,727
Expected benefit payments in 2022	102,183
Expected benefit payments in 2023	104,792
Expected benefit payments in 2024	107,078
Expected benefit payments in 2025	110,810
Expected benefit payments 2026-2029	587,220
SERPA Benefits
Defined Benefit Plan, Expected Future Benefit Payment [Abstract]
Expected benefit payments in 2021	8,813
Expected benefit payments in 2022	1,684
Expected benefit payments in 2023	1,955
Expected benefit payments in 2024	1,919
Expected benefit payments in 2025	1,818
Expected benefit payments 2026-2029	11,071
Postretirement Health Coverage
Defined Benefit Plan, Expected Future Benefit Payment [Abstract]
Expected benefit payments in 2021	23,444
Expected benefit payments in 2022	23,707
Expected benefit payments in 2023	23,775
Expected benefit payments in 2024	23,465
Expected benefit payments in 2025	23,157
Expected benefit payments 2026-2029	$ 108,384

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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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