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EMPLOYEE RETIREMENT PLANS - Assumptions - General Disclosures (Details) - Defined-benefit pension plans | 12 Months Ended | 120 Months Ended
--- | --- | ---
Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2016
Assumptions |  |  |  |
Discount rate for obligations (as a percent) | 3.80% | 3.30% | 3.50% | 3.50%
Expected return on plan assets (as a percent) | 7.00% | 7.25% | 7.25% |
Actual annual rate of return on pension plan assets (as a percent) | 4.90% | 13.90% | 8.30% | 7.90%
Equity securities |  |  |  |
Assumptions |  |  |  |
Asset allocation (as a percent) | 35.00% |  |  |
Debt securities |  |  |  |
Assumptions |  |  |  |
Asset allocation (as a percent) | 45.00% |  |  |
Alternative investments |  |  |  |
Assumptions |  |  |  |
Asset allocation (as a percent) | 20.00% |  |  |
Minimum |  |  |  |
Assumptions |  |  |  |
Discount rate for obligations (as a percent) | 1.50% | 1.50% | 1.50% | 1.50%
Liabilities having a discount rate for obligations (as a percent) | 4.10% | 3.40% | 3.80% | 3.80%
Maximum |  |  |  |
Assumptions |  |  |  |
Discount rate for obligations (as a percent) | 4.20% | 3.60% | 4.00% | 4.00%

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- Definition Actual rate of return on plan assets reflecting the average rate of earnings on the funds invested for the benefits included in the benefit obligation. + References No definition available. + Details
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- Definition The interest rate used to adjust for the time value of money for the plan applied to the most significant portion of the liabilities. + 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/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (k)(1) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
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- Definition Weighted average rate of return on plan assets, reflecting average rate of earnings expected on existing plan assets and expected contributions, used to determine net periodic benefit cost of defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (k)(3) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
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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/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(5)(i) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
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