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BENEFIT PLANS - Weighted-average Assumptions Used to Determine Benefit Obligations (Details) | 12 Months Ended
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Dec. 31, 2020 | Dec. 31, 2019
Pension Benefits [Member] |  |
Weighed average assumption used in calculating benefit obligations [Abstract] |  |
Discount rate | 2.80% | 3.50%
Expected return on plan assets | 7.00% | 7.00%
Rate of compensation increase | 3.50% | 3.50%
Post-retirement Benefits [Member] |  |
Weighed average assumption used in calculating benefit obligations [Abstract] |  |
Discount rate | 2.80% | 3.60%

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- Definition An assumption as to the rate of return on plan assets reflecting the average rate of earnings expected on the funds invested or to be invested to provide for the benefits included in the benefit obligation. + References No definition available. + Details
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- Definition Weighted average rate for present value of future retirement benefits cash flows, used to determine benefit obligation of defined benefit plan. + 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 (k)(1) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 + Details
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- Definition Weighted average rate increase of compensation, used to determine benefit obligation of defined benefit plan. Plan includes, but is not limited to, pay-related defined benefit plan. + 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 (k)(2) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 + Details
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- Details
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