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EMPLOYEE RETIREMENT PLANS - Qualified Defined-benefit Pension Plan Weighted Average Asset Allocation (Details) - Qualified | Dec. 31, 2020 | Dec. 31, 2019
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Plan Assets |  |
Weighted average asset allocation (as a percent) | 100.00% | 100.00%
Equity securities |  |
Plan Assets |  |
Weighted average asset allocation (as a percent) | 15.00% | 41.00%
Debt securities |  |
Plan Assets |  |
Weighted average asset allocation (as a percent) | 49.00% | 54.00%
Other |  |
Plan Assets |  |
Weighted average asset allocation (as a percent) | 36.00% | 5.00%

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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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