Pension Plan and Employee Benefits - Projected Benefit Payments and Projected Receipts (Details) $ in Thousands	Dec. 31, 2020 USD ($)
PENSION BENEFITS
For the year ending Dec. 31,
2021	$ 25,568
2022	26,904
2023	28,064
2024	29,140
2025	30,336
Next five years	164,801
OTHER BENEFITS
For the year ending Dec. 31,
2021	4,516
2022	4,551
2023	4,515
2024	4,533
2025	4,497
Next five years	21,676
SERP BENEFITS
For the year ending Dec. 31,
2021	4,764
2022	4,756
2023	4,809
2024	4,867
2025	5,000
Next five years	$ 25,178

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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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