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EMPLOYEE BENEFIT PLANS - Weighted average asset allocation by asset category along with target allocation (Details) | Dec. 31, 2019 | Dec. 31, 2018
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Minimum | Investments measured at net asset value |  |
EMPLOYEE BENEFIT PLANS |  |
Target Allocation for 2020 | 0.00% |
Retirement Income Plan |  |
EMPLOYEE BENEFIT PLANS |  |
Percentage of Plan Assets | 100.00% | 100.00%
Target Allocation for 2020 | 100.00% |
Retirement Income Plan | Cash and Cash Equivalents |  |
EMPLOYEE BENEFIT PLANS |  |
Percentage of Plan Assets | 1.30% | 3.00%
Retirement Income Plan | Domestic Equity Securities |  |
EMPLOYEE BENEFIT PLANS |  |
Percentage of Plan Assets | 0.00% | 39.50%
Retirement Income Plan | International Equity Securities |  |
EMPLOYEE BENEFIT PLANS |  |
Percentage of Plan Assets | 0.00% | 19.00%
Retirement Income Plan | Fixed Income Securities |  |
EMPLOYEE BENEFIT PLANS |  |
Percentage of Plan Assets | 91.70% | 29.10%
Retirement Income Plan | Investments measured at net asset value |  |
EMPLOYEE BENEFIT PLANS |  |
Percentage of Plan Assets | 7.00% | 9.40%
Retirement Income Plan | Minimum | Cash and Cash Equivalents |  |
EMPLOYEE BENEFIT PLANS |  |
Target Allocation for 2020 | 0.00% |
Retirement Income Plan | Minimum | Domestic Equity Securities |  |
EMPLOYEE BENEFIT PLANS |  |
Target Allocation for 2020 | 0.00% |
Retirement Income Plan | Minimum | International Equity Securities |  |
EMPLOYEE BENEFIT PLANS |  |
Target Allocation for 2020 | 0.00% |
Retirement Income Plan | Minimum | Fixed Income Securities |  |
EMPLOYEE BENEFIT PLANS |  |
Target Allocation for 2020 | 15.00% |
Retirement Income Plan | Maximum | Cash and Cash Equivalents |  |
EMPLOYEE BENEFIT PLANS |  |
Target Allocation for 2020 | 5.00% |
Retirement Income Plan | Maximum | Domestic Equity Securities |  |
EMPLOYEE BENEFIT PLANS |  |
Target Allocation for 2020 | 40.00% |
Retirement Income Plan | Maximum | International Equity Securities |  |
EMPLOYEE BENEFIT PLANS |  |
Target Allocation for 2020 | 20.00% |
Retirement Income Plan | Maximum | Fixed Income Securities |  |
EMPLOYEE BENEFIT PLANS |  |
Target Allocation for 2020 | 100.00% |
Retirement Income Plan | Maximum | Investments measured at net asset value |  |
EMPLOYEE BENEFIT PLANS |  |
Target Allocation for 2020 | 12.00% |

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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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