Benefit Plans: (Weighted-Average Assumptions to Determine Benefit Obligations) (Details) |
Dec. 31, 2023 |
Dec. 31, 2022 |
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| Pension Plan | ||
| Defined Benefit Plan Disclosure [Line Items] | ||
| Discount rate (as a percent) | 2.28% | 3.03% |
| Rate of compensation increase (as a percent) | 2.05% | 1.98% |
| Interest crediting rate (as a percent) | 2.99% | 2.97% |
| Postretirement | ||
| Defined Benefit Plan Disclosure [Line Items] | ||
| Discount rate (as a percent) | 5.19% | 5.89% |
| Heath care cost trend rate assumed for next year (as a percent) | 6.54% | 6.14% |
| Ultimate trend rate (as a percent) | 4.49% | 4.78% |
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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. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Weighted average rate increase of compensation, used to determine benefit obligation of defined benefit plan. Plan includes, but is not limited to, pay-related defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Weighted-average interest crediting rate used to determine benefit obligation of defined benefit plan. Plan includes, but is not limited to, cash balance and other defined benefit plans with promised interest crediting rate. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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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. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Ultimate trend rate for health care cost for defined benefit postretirement plan. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Details
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- Details
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