RETIREMENT BENEFITS Retirement Benefits - Estimate of Expected Benefit Payments (Details) - Other Postretirement Benefits Plan [Member] $ in Thousands	Dec. 31, 2020 USD ($)
2021	$ 5,000
2022	5,000
2023	6,000
2024	6,000
2025	5,000
Thereafter	$ 25,000

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

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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- Definition

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

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- Definition

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

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- Definition

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

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- Definition

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

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