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Benefit Plans (Tables) | 12 Months Ended
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Dec. 31, 2023
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items] |
Components of net periodic benefit cost | The following tables 11.1, 11.2, and 11.3 provide the components of aggregate annual net periodic benefit cost for each of the years ended December 31, 2023, 2022, and 2021 and changes in the benefit obligation and the funded status of the pension, supplemental executive retirement and other postretirement benefit plans as recognized in the consolidated balance sheets as of December 31, 2023 and 2022.
Components of net periodic benefit cost
Table | 11.1 |  |  |  |  |  |  |  |  |  |  |  |
|  | Pension and Supplemental Executive Retirement Plans |  | Other Postretirement Benefits
(In thousands) |  | 12/31/2023 |  | 12/31/2022 |  | 12/31/2021 |  | 12/31/2023 |  | 12/31/2022 |  | 12/31/2021
Company Service Cost |  | $ | — |  |  | $ | 7,153 |  |  | $ | 7,569 |  |  | $ | 1,497 |  |  | $ | 1,307 |  |  | $ | 1,508 |
Interest Cost |  | 13,787 |  |  | 12,461 |  |  | 11,276 |  |  | 1,633 |  |  | 694 |  |  | 648 |
Expected Return on Plan Assets |  | (13,517) |  |  | (18,064) |  |  | (20,657) |  |  | (8,235) |  |  | (10,502) |  |  | (8,863) |
Amortization of: |  |  |  |  |  |  |  |  |  |  |  |
Net Transition Obligation (Asset) |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |
Prior Service Cost (Credit) |  | 345 |  |  | (163) |  |  | (239) |  |  | 1,861 |  |  | 489 |  |  | 213 |
Net Actuarial Losses (Gains) |  | 2,185 |  |  | 5,726 |  |  | 5,490 |  |  | (150) |  |  | (3,103) |  |  | (1,697) |
Cost of Settlements and Curtailments |  | 9,749 |  |  | 13,801 |  |  | 6,012 |  |  | — |  |  | — |  |  | — |
Net Periodic Benefit Cost (Benefit) |  | $ | 12,549 |  |  | $ | 20,914 |  |  | $ | 9,451 |  |  | $ | (3,394) |  |  | $ | (11,115) |  |  | $ | (8,191) |
Development of funded status |
Development of funded status
Table | 11.2 |  |  |  |  |  |  |  |
|  | Pension and Supplemental Executive Retirement Plans |  | Other Postretirement Benefits
(In thousands) |  | 12/31/2023 |  | 12/31/2022 |  | 12/31/2023 |  | 12/31/2022
Actuarial Value of Benefit Obligations |  |  |  |  |  |  |  |
Measurement Date |  | 12/31/2023 |  | 12/31/2022 |  | 12/31/2023 |  | 12/31/2022
Accumulated Benefit Obligation |  | $ | 261,330 |  |  | $ | 274,975 |  |  | $ | 30,238 |  |  | $ | 29,580 |
Funded Status/Asset (Liability) on the Consolidated Balance Sheet |  |  |  |  |  |  |  |
Benefit Obligation |  | $ | (261,330) |  |  | $ | (274,975) |  |  | $ | (30,238) |  |  | $ | (29,580) |
Plan Assets at Fair Value |  | 235,612 |  |  | 250,674 |  |  | 134,371 |  |  | 111,154 |
Funded Status - Overfunded/Asset |  | N/A |  | N/A |  | $ | 104,133 |  |  | $ | 81,574 |
Funded Status - Underfunded/Liability |  | (25,718) |  |  | (24,301) |  |  | N/A |  | N/A
Accumulated other comprehensive (income) loss
Table | 11.3 |  |  |  |  |  |  |  |
|  | Pension and Supplemental Executive Retirement Plans |  | Other Postretirement Benefits
(In thousands) |  | 12/31/2023 |  | 12/31/2022 |  | 12/31/2023 |  | 12/31/2022
Net Actuarial Losses (Gains) |  | $ | 79,309 |  |  | $ | 89,711 |  |  | $ | (30,804) |  |  | $ | (13,781) |
Prior Service Cost (Credit) |  | 2,900 |  |  | 3,245 |  |  | 11,041 |  |  | 13,249 |
Net Transition Obligation (Asset) |  | — |  |  | — |  |  | — |  |  | — |
Total at Year End |  | $ | 82,209 |  |  | $ | 92,956 |  |  | $ | (19,763) |  |  | $ | (532) |
Change in projected benefit obligation | Table 11.4 shows the changes in the projected benefit obligation for the years ended December 31, 2023 and 2022.
Change in projected benefit / accumulated benefit
Table | 11.4 |  |  |  |  |  |  |  |
|  | Pension and Supplemental Executive Retirement Plans |  | Other Postretirement Benefits
(In thousands) |  | 12/31/2023 |  | 12/31/2022 |  | 12/31/2023 |  | 12/31/2022
Benefit Obligation at Beginning of Year |  | $ | 274,975 |  |  | $ | 391,698 |  |  | $ | 29,580 |  |  | $ | 25,635 |
Company Service Cost |  | — |  |  | 7,153 |  |  | 1,497 |  |  | 1,307 |
Interest Cost |  | 13,787 |  |  | 12,461 |  |  | 1,633 |  |  | 694 |
Plan Participants' Contributions |  | — |  |  | — |  |  | 311 |  |  | 463 |
Net Actuarial Losses (Gains) |  | 16,995 |  |  | (83,240) |  |  | 1,294 |  |  | (8,123) |
Benefit Payments from Fund |  | (13,549) |  |  | (13,165) |  |  | (3,439) |  |  | (1,504) |
Benefit and Settlement Payments Paid Directly by Company |  | (384) |  |  | (114) |  |  | — |  |  | — |
Plan Amendments |  | — |  |  | 3,247 |  |  | (346) |  |  | 11,278 |
Curtailments |  | — |  |  | (352) |  |  | — |  |  | — |
Settlement Payments from Fund (1) |  | (30,494) |  |  | (42,713) |  |  | — |  |  | — |
Other Adjustment |  | — |  |  | — |  |  | (292) |  |  | (170) |
Benefit Obligation at End of Year |  | $ | 261,330 |  |  | $ | 274,975 |  |  | $ | 30,238 |  |  | $ | 29,580 |
(1)Represents lump sum payments from our pension plan to eligible participants, who were former employees with vested benefits.
Changes in fair value of plan assets and other comprehensive income (loss) | Tables 11.5 and 11.6 shows the changes in the fair value of the net assets available for plan benefits and changes in other comprehensive income (loss) for the years ended December 31, 2023 and 2022.
Change in plan assets
Table | 11.5 |  |  |  |  |  |  |  |
|  | Pension and Supplemental Executive Retirement Plans |  | Other Postretirement Benefits
(In thousands) |  | 12/31/2023 |  | 12/31/2022 |  | 12/31/2023 |  | 12/31/2022
Fair Value of Plan Assets at Beginning of Year |  | $ | 250,674 |  |  | $ | 391,555 |  |  | $ | 111,154 |  |  | $ | 140,839 |
Actual Return on Plan Assets |  | 28,981 |  |  | (91,303) |  |  | 26,703 |  |  | (28,088) |
Company Contributions |  | 384 |  |  | 6,414 |  |  | — |  |  | — |
Plan Participants' Contributions |  | — |  |  | — |  |  | 311 |  |  | 463 |
Benefit Payments from Fund |  | (13,549) |  |  | (13,165) |  |  | (3,439) |  |  | (1,504) |
Benefit and Settlement Payments Paid Directly by Company |  | (384) |  |  | (114) |  |  | — |  |  | — |
Settlement Payments from Fund |  | (30,494) |  |  | (42,713) |  |  | — |  |  | — |
Other Adjustment |  | — |  |  | — |  |  | (358) |  |  | (556) |
Fair Value of Plan Assets at End of Year |  | $ | 235,612 |  |  | $ | 250,674 |  |  | $ | 134,371 |  |  | $ | 111,154 |
Change in accumulated other comprehensive income (loss) ("AOCI") |  |  |  |  |  |
Table | 11.6 |  |  |  |  |  |  |  |
|  | Pension and Supplemental Executive Retirement Plans |  | Other Postretirement Benefits
(In thousands) |  | 12/31/2023 |  | 12/31/2022 |  | 12/31/2023 |  | 12/31/2022
AOCI in Prior Year |  | $ | 92,956 |  |  | $ | 83,298 |  |  | $ | (532) |  |  | $ | (44,891) |
Increase (Decrease) in AOCI |  |  |  |  |  |  |  |
Recognized during year - Prior Service (Cost) Credit |  | (345) |  |  | 745 |  |  | (1,861) |  |  | (489) |
Recognized during year - Net Actuarial (Losses) Gains |  | (11,933) |  |  | (20,109) |  |  | 150 |  |  | 3,103 |
Occurring during year - Prior Service Cost |  | — |  |  | 3,247 |  |  | (346) |  |  | 11,277 |
Occurring during year - Net Actuarial Losses (Gains) |  | 1,531 |  |  | 25,775 |  |  | (17,174) |  |  | 30,468 |
AOCI in Current Year |  | $ | 82,209 |  |  | $ | 92,956 |  |  | $ | (19,763) |  |  | $ | (532) |
Actuarial assumptions | The projected benefit obligations, net periodic benefit costs and accumulated postretirement benefit obligation for the plans were determined using the following weighted average assumptions.
Actuarial assumptions
Table | 11.7 |  |  |  |  |  |  |  |
|  | Pension and Supplemental Executive Retirement Plans |  | Other Postretirement Benefits
|  | 12/31/2023 |  | 12/31/2022 |  | 12/31/2023 |  | 12/31/2022
Weighted-Average Assumptions Used to Determine |  |  |  |  |  |  |  |
Benefit Obligations at year end |  |  |  |  |  |  |  |
1. Discount Rate |  | 5.20 | % |  | 5.60 | % |  | 5.20 | % |  | 5.60 | %
2. Rate of Compensation Increase |  | N/A |  | 3.00 | % |  | N/A |  | N/A
3. Cash balance interest crediting rate |  | 4.03 | % |  | 3.97 | % |  | N/A |  | N/A
Weighted-Average Assumptions Used to Determine |  |  |  |  |  |  |  |
Net Periodic Benefit Cost for Year |  |  |  |  |  |  |  |
1. Discount Rate |  | 5.50 | % |  | 3.70 | % |  | 5.60 | % |  | 2.85 | %
2. Expected Long-term Return on Plan Assets |  | 6.00 | % |  | 5.25 | % |  | 7.50 | % |  | 7.50 | %
3. Rate of Compensation Increase |  | N/A |  | 3.00 | % |  | N/A |  | N/A
Assumed Health Care Cost Trend Rates at year end |  |  |  |  |  |  |  |
1. Health Care Cost Trend Rate Assumed for Next Year |  | N/A |  | N/A |  | 6.75 | % |  | 7.00 | %
2. Rate to Which the Cost Trend Rate is Assumed to Decline (Ultimate Trend Rate) |  | N/A |  | N/A |  | 5.00 | % |  | 5.00 | %
3. Year That the Rate Reaches the Ultimate Trend Rate |  | N/A |  | N/A |  | 2031 |  | 2031
Year-end asset allocations of the plans | The year-end asset allocations of the plans are shown in table 11.8 below.
Plan assets
Table | 11.8 |  |  |  |  |  |  |  |
|  | Pension Plan |  | Other Postretirement Benefits
|  | 12/31/2023 |  | 12/31/2022 |  | 12/31/2023 |  | 12/31/2022
Equity Securities |  | 21 | % |  | 20 | % |  | 100 | % |  | 100 | %
Debt Securities |  | 79 | % |  | 80 | % |  | — | % |  | — | %
Total |  | 100 | % |  | 100 | % |  | 100 | % |  | 100 | %
Schedule of investment allocation strategies | The equity investments use combinations of mutual funds, ETFs, and pooled equity account structures focused on the following strategies:
Strategy |  | Objective |  | Investment types
Return seeking growth |  | Funded ratio improvement over the long term |  | ● | Global quality growth
|  | ● | Global low volatility
Return seeking bridge |  | Downside protection in the event of a declining equity market |  | ● | Enduring asset
|  | ● | Durable company
Minimum and maximum allocation ranges for fixed income securities and equity securities | The primary focus in developing asset allocation ranges for the portfolio is the assessment of the portfolio's investment objectives and the level of risk that is acceptable to obtain those objectives. To achieve these objectives the minimum and maximum allocation ranges for fixed income securities and equity securities are:
| Minimum |  | Maximum
Equities (long only) | 70 | % |  | 100 | %
Real estate | 0 | % |  | 15 | %
Commodities | 0 | % |  | 10 | %
Fixed income/Cash | 0 | % |  | 10 | %
Schedule of expected future benefit payments | Expected future benefit payments from the plans are shown in Table 11.11 below.
Expected future benefit payments
Table | 11.11 |  |  |  |
|  | Pension and Supplemental Executive Retirement Plans |  | Other Postretirement Benefits
(In thousands) |  | 12/31/2023 |  | 12/31/2023
Current + 1 |  | 23,110 |  |  | 2,761 |
Current + 2 |  | 22,771 |  |  | 2,849 |
Current + 3 |  | 23,116 |  |  | 2,715 |
Current + 4 |  | 23,226 |  |  | 2,630 |
Current + 5 |  | 22,236 |  |  | 2,825 |
Current + 6 - 10 |  | 100,929 |  |  | 15,326 |
Pension Plan |
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items] |
Schedule of fair value of plan assets | The pension plan assets and related accrued investment income at fair value, by hierarchy level, as of December 31, 2023 and 2022, are shown in tables 11.9a and 11.9b below. There were no securities valued using Level 3 inputs.
Pension plan assets at fair value as of December 31, 2023
Table | 11.9a |  |  |  |  |  |
(In thousands) |  | Level 1 |  | Level 2 |  | Total
Domestic mutual funds |  | $ | 2,836 |  |  | $ | — |  |  | $ | 2,836 |
U.S. government securities |  | 10,301 |  |  | — |  |  | 10,301 |
Corporate debt securities |  |  |  |  |  |
Corporate debt securities and other |  | — |  |  | 145,908 |  |  | 145,908 |
Non-government foreign debt securities |  | — |  |  | 21,843 |  |  | 21,843 |
Municipal bonds |  | — |  |  | 9,220 |  |  | 9,220 |
Pooled equity accounts |  | — |  |  | 45,504 |  |  | 45,504 |
Total Assets at fair value |  | $ | 13,137 |  |  | $ | 222,475 |  |  | $ | 235,612 |
Pension plan assets at fair value as of December 31, 2022
Table | 11.9b |  |  |  |  |  |
(In thousands) |  | Level 1 |  | Level 2 |  | Total
Domestic mutual funds |  | $ | 67 |  |  | $ | — |  |  | $ | 67 |
U.S. government securities |  | 13,328 |  |  | — |  |  | 13,328 |
Corporate debt Securities |  |  |  |  |  |
Corporate debt securities and other |  | — |  |  | 146,854 |  |  | 146,854 |
Non-government foreign debt securities |  | — |  |  | 20,793 |  |  | 20,793 |
Municipal bonds |  | — |  |  | 18,336 |  |  | 18,336 |
Pooled equity accounts |  | — |  |  | 51,296 |  |  | 51,296 |
Total Assets at fair value |  | $ | 13,395 |  |  | $ | 237,279 |  |  | $ | 250,674 |
Other Postretirement Benefit Plan |
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items] |
Schedule of fair value of plan assets | Tables 11.10a and 11.10b set forth the other postretirement benefits plan assets at fair value as of December 31, 2023 and 2022. All are Level 1 assets.
Other postretirement benefits plan assets at fair value as of December 31, 2023
Table | 11.10a |  |
(In thousands) |  | Level 1
Domestic mutual funds |  | $ | 109,575 |
International mutual funds |  | 24,796 |
Total Assets at fair value |  | $ | 134,371 |
Other postretirement benefits plan assets at fair value as of December 31, 2022
Table | 11.10b |  |
(In thousands) |  | Level 1
Domestic mutual funds |  | $ | 89,584 |
International mutual funds |  | 21,570 |
Total Assets at fair value |  | $ | 111,154 |

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