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PENSION AND OTHER POSTRETIREMENT PLANS - Target Allocations for Plan Assets (Details) | 12 Months Ended |
--- | --- | ---
Dec. 31, 2020 | Dec. 31, 2019
Target allocations for Plan assets |  |
Percentage of Plan Assets | 100.00% | 100.00%
Cash and cash equivalents |  |
Target allocations for Plan assets |  |
Percentage of Plan Assets | 5.60% | 3.60%
Weighted-Average Expected Long-term Rate of Return (as a percent) | 0.00% |
Cash and cash equivalents | Minimum |  |
Target allocations for Plan assets |  |
Target Allocation 2021 (as a percent) | 0.00% |
Cash and cash equivalents | Maximum |  |
Target allocations for Plan assets |  |
Target Allocation 2021 (as a percent) | 5.00% |
Equity Securities |  |
Target allocations for Plan assets |  |
Percentage of Plan Assets | 56.80% | 57.90%
Weighted-Average Expected Long-term Rate of Return (as a percent) | 9.50% |
Equity Securities | Minimum |  |
Target allocations for Plan assets |  |
Target Allocation 2021 (as a percent) | 45.00% |
Equity Securities | Maximum |  |
Target allocations for Plan assets |  |
Target Allocation 2021 (as a percent) | 65.00% |
Fixed income securities |  |
Target allocations for Plan assets |  |
Percentage of Plan Assets | 37.60% | 38.50%
Weighted-Average Expected Long-term Rate of Return (as a percent) | 5.00% |
Fixed income securities | Minimum |  |
Target allocations for Plan assets |  |
Target Allocation 2021 (as a percent) | 30.00% |
Fixed income securities | Maximum |  |
Target allocations for Plan assets |  |
Target Allocation 2021 (as a percent) | 50.00% |

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- Definition Percentage of target investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 55 -Paragraph 17 -URI http://asc.fasb.org/extlink&oid=118257860&loc=d3e4179-114921 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(i) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 + Details
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- Definition Percentage of actual investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(i) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 + Details
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