Pension and Other Postretirement Benefits - Benefits Expected to be Paid in Subsequent Years from Our Pension and Other Postretirement as Well as Medicare Subsidy Receipts (Details) $ in Thousands	Dec. 31, 2020 USD ($)
Pension Benefits
Pension And Other Employee Benefit Plans [Line Items]
2021	$ 19,497
2022	19,044
2023	20,320
2024	21,247
2025	19,417
2026-2030	99,881
Total	199,406
Other Benefits
Pension And Other Employee Benefit Plans [Line Items]
2021	1,460
2022	1,457
2023	1,458
2024	1,463
2025	1,466
2026-2030	7,413
Total	$ 14,717

Defined Benefit Plan Expected Future Benefit Payments In Next Ten Years

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- Definition

Pension And Other Employee Benefit Plans [Line Items]

+ References

No definition available.

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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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- Definition

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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