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BENEFIT PLANS: Benefit Plans Narrative (Details) - USD ($) | 11 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2074 | Dec. 31, 2028 | Dec. 31, 2027 | Dec. 31, 2026 | Dec. 31, 2025 | Dec. 31, 2024 | Dec. 31, 2023
Defined Benefit Plan, Net Periodic Benefit Cost |  |  |  |  |  |  |
Fair Value, All Levels Transfers, Amount |  |  |  |  | $ 0 | $ 0 |
Employer contributions |  |  |  |  | 10,900,000 | 10,400,000 | $ 9,800,000
Supplemental Unemployment Benefits, Disability Related Benefits |  |  |  |  | $ 1,000,000 | $ 3,000,000 |
Pension Plan |  |  |  |  |  |  |
Defined Benefit Plan, Net Periodic Benefit Cost |  |  |  |  |  |  |
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Discount Rate |  |  |  |  | 5.70% | 5.10% | 5.45%
Employer contributions |  |  |  |  | $ 20,000,000 | $ 20,000,000 |
Postretirement Benefits |  |  |  |  |  |  |
Defined Benefit Plan Disclosure |  |  |  |  |  |  |
Postretirement Benefit, Medical Trend Rate |  |  |  |  | 6.20% | 7.10% | 6.70%
Postretirement Benefit, Dental Trend Rate |  |  |  |  | 4.00% | 3.50% | 3.50%
Defined Benefit Plan, Net Periodic Benefit Cost |  |  |  |  |  |  |
Health Care Cost Trend Rate Assumed for Next Fiscal Year |  |  |  |  | 4.00% | 3.50% |
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Discount Rate |  |  |  |  | 5.70% | 5.15% | 5.45%
Senior Management Security Plan |  |  |  |  |  |  |
Defined Benefit Plan Disclosure |  |  |  |  |  |  |
Executive Deferred Compensation Plan Assets |  |  |  |  | $ 172,100,000 | $ 159,100,000 |
Defined Benefit Plan, Net Periodic Benefit Cost |  |  |  |  |  |  |
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Discount Rate |  |  |  |  | 5.70% | 5.20% | 5.50%
Employer contributions |  |  |  |  | $ 0 | $ 0 |
Forecast | Pension Plan |  |  |  |  |  |  |
Defined Benefit Plan, Net Periodic Benefit Cost |  |  |  |  |  |  |
Defined Benefit Plan, Minimum Funding Requirement for Next Fiscal Year |  |  |  | $ 0 |  |  |
Defined Benefit Plan, Estimated Future Employer Contributions in Next Fiscal Year |  |  |  | $ 30,000,000 |  |  |
Forecast | Postretirement Benefits |  |  |  |  |  |  |
Defined Benefit Plan Disclosure |  |  |  |  |  |  |
Postretirement Benefit, Dental Trend Rate |  |  | 4.00% |  |  |  |
Defined Benefit Plan, Net Periodic Benefit Cost |  |  |  |  |  |  |
Health Care Cost Trend Rate Assumed For Year Two |  |  |  | 7.00% |  |  |
Health Care Cost Trend Rate Assumed for Year Three |  |  | 6.20% |  |  |  |
Health Care Cost Trend Rate Assumed for Year Four | 3.80% | 5.50% |  |  |  |  |

X
- Definition The assumed health care cost trend rate for the second fiscal year used to measure the expected cost of benefits covered by the plan (gross eligible charges). This is based upon the annual rate of change in the cost of health care benefits currently provided by the postretirement benefit plan, due to factors other than changes in the composition of the plan population by age and dependency status. + References No definition available. + Details
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- Definition The assumed health care cost trend rate for the fourth fiscal year used to measure the expected cost of benefits covered by the plan (gross eligible charges). This is based upon the annual rate of change in the cost of health care benefits currently provided by the postretirement benefit plan, due to factors other than changes in the composition of the plan population by age and dependency status. + References No definition available. + Details
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- Definition The assumed health care cost trend rate for the third fiscal year used to measure the expected cost of benefits covered by the plan (gross eligible charges). This is based upon the annual rate of change in the cost of health care benefits currently provided by the postretirement benefit plan, due to factors other than changes in the composition of the plan population by age and dependency status. + References No definition available. + Details
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- Definition Carrying amount as of the balance sheet date of assets held under deferred compensation agreements. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 210 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(17)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1 + Details
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- Definition Assumed rate, for next fiscal year, based on annual change in cost of health care cost benefits used to measure expected cost of benefits covered by defined benefit postretirement plan. Factors include, but are not limited to, estimate of health care inflation, change in health care utilization or delivery pattern, technological advances, and change in health status of participant. Excludes factors for change in composition of plan population by age and dependency status. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (l) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-1 + Details
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