v3.20.1

Employee Benefit Plans (Tables) | 12 Months Ended
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Dec. 31, 2019
Retirement Benefits [Abstract] |
Changes In Benefit Obligations And Plan Assets | The following table presents the changes in benefit obligations and plan assets for pension benefits and other postretirement benefits, as well as the end-of-period accumulated benefit obligation for the years ended December 31, 2018 and 2019 (in thousands):
|  | Pension Benefits |  | Other Postretirement Benefits
|  | 2018 |  | 2019 |  | 2018 |  | 2019
Change in benefit obligations: |  |  |  |  |  |  |  |
Benefit obligations at beginning of year |  | $ | 297,856 |  |  | $ | 308,949 |  |  | $ | 12,760 |  |  | $ | 12,080 |
Service cost |  | 38,167 |  |  | 25,406 |  |  | 243 |  |  | 193 |
Interest cost |  | 14,907 |  |  | 12,163 |  |  | 416 |  |  | 507 |
Plan participants’ contributions |  | — |  |  | — |  |  | 357 |  |  | 564 |
Actuarial (gain) loss |  | (21,375 | ) |  | 54,171 |  |  | (599 | ) |  | 3,300 |
Benefits paid |  | (14,356 | ) |  | (11,409 | ) |  | (1,097 | ) |  | (1,437 | )
Settlement payments |  | (6,250 | ) |  | (8,040 | ) |  | — |  |  | — |
Benefit obligations at end of year |  | 308,949 |  |  | 381,240 |  |  | 12,080 |  |  | 15,207 |
Change in plan assets: |  |  |  |  |  |  |  |
Fair value of plan assets at beginning of year |  | 198,686 |  |  | 197,590 |  |  | — |  |  | — |
Employer contributions |  | 31,717 |  |  | 31,630 |  |  | 740 |  |  | 873 |
Plan participants’ contributions |  | — |  |  | — |  |  | 357 |  |  | 564 |
Actual (loss) return on plan assets |  | (12,207 | ) |  | 39,522 |  |  | — |  |  | — |
Benefits paid |  | (14,356 | ) |  | (11,409 | ) |  | (1,097 | ) |  | (1,437 | )
Settlement payments |  | (6,250 | ) |  | (8,040 | ) |  | — |  |  | — |
Fair value of plan assets at end of year |  | 197,590 |  |  | 249,293 |  |  | — |  |  | — |
Funded status at end of year |  | $ | (111,359 | ) |  | $ | (131,947 | ) |  | $ | (12,080 | ) |  | $ | (15,207 | )
Accumulated benefit obligations |  | $ | 208,840 |  |  | $ | 274,353 |  |  |  |  |
Amounts Recognized In Consolidated Balance Sheets | Amounts recognized in the consolidated balance sheets included in these financial statements were as follows (in thousands):
|  | Pension Benefits |  | Other Postretirement Benefits
|  | 2018 |  | 2019 |  | 2018 |  | 2019
Amounts recognized in consolidated balance sheets: |  |  |  |  |  |  |  |
Current accrued benefit cost |  | $ | — |  |  | $ | — |  |  | $ | 859 |  |  | $ | 1,162 |
Long-term pension and benefits |  | 111,359 |  |  | 131,947 |  |  | 11,221 |  |  | 14,045 |
|  | 111,359 |  |  | 131,947 |  |  | 12,080 |  |  | 15,207 |
Accumulated other comprehensive loss: |  |  |  |  |  |  |  |
Net actuarial loss |  | (91,669 | ) |  | (107,625 | ) |  | (5,409 | ) |  | (8,378 | )
Prior service credit |  | 3,067 |  |  | 2,886 |  |  | — |  |  | — |
|  | (88,602 | ) |  | (104,739 | ) |  | (5,409 | ) |  | (8,378 | )
Net amount of liabilities and accumulated other comprehensive loss recognized in consolidated balance sheets |  | $ | 22,757 |  |  | $ | 27,208 |  |  | $ | 6,671 |  |  | $ | 6,829 |
Consolidated Net Periodic Benefit Costs | Net periodic benefit expense for the years ended December 31, 2017, 2018 and 2019 was as follows (in thousands):
|  | Pension Benefits |  | Other Postretirement Benefits
|  | 2017 |  | 2018 |  | 2019 |  | 2017 |  | 2018 |  | 2019
Components of net periodic pension and postretirement benefit expense: |  |  |  |  |  |  |  |  |  |  |  |
Service cost |  | $ | 20,497 |  |  | $ | 38,167 |  |  | $ | 25,406 |  |  | $ | 243 |  |  | $ | 243 |  |  | $ | 193 |
Interest cost |  | 9,865 |  |  | 14,907 |  |  | 12,163 |  |  | 475 |  |  | 416 |  |  | 507 |
Expected return on plan assets |  | (10,266 | ) |  | (12,090 | ) |  | (9,401 | ) |  | — |  |  | — |  |  | — |
Amortization of prior service credit |  | (181 | ) |  | (181 | ) |  | (181 | ) |  | — |  |  | — |  |  | — |
Amortization of actuarial loss |  | 5,622 |  |  | 9,763 |  |  | 5,489 |  |  | 749 |  |  | 589 |  |  | 331 |
Settlement cost |  | 2,460 |  |  | 1,964 |  |  | 2,606 |  |  | — |  |  | — |  |  | — |
Net periodic expense |  | $ | 27,997 |  |  | $ | 52,530 |  |  | $ | 36,082 |  |  | $ | 1,467 |  |  | $ | 1,248 |  |  | $ | 1,031 |
Other Changes In Plan Assets And Benefit Obligations Recognized In Other Comprehensive Loss | Changes in plan assets and benefit obligations recognized in other comprehensive income (loss) during 2017, 2018 and 2019 were as follows (in thousands):
|  | Pension Benefits |  | Other Postretirement Benefits
|  | 2017 |  | 2018 |  | 2019 |  | 2017 |  | 2018 |  | 2019
Beginning balance |  | $ | (58,584 | ) |  | $ | (97,226 | ) |  | $ | (88,602 | ) |  | $ | (7,881 | ) |  | $ | (6,597 | ) |  | $ | (5,409 | )
Net actuarial gain (loss) |  | (46,543 | ) |  | (2,922 | ) |  | (24,051 | ) |  | 535 |  |  | 599 |  |  | (3,300 | )
Amortization of prior service credit |  | (181 | ) |  | (181 | ) |  | (181 | ) |  | — |  |  | — |  |  | — |
Amortization of actuarial loss |  | 5,622 |  |  | 9,763 |  |  | 5,489 |  |  | 749 |  |  | 589 |  |  | 331 |
Settlement cost |  | 2,460 |  |  | 1,964 |  |  | 2,606 |  |  | — |  |  | — |  |  | — |
Amount recognized in other comprehensive loss |  | (38,642 | ) |  | 8,624 |  |  | (16,137 | ) |  | 1,284 |  |  | 1,188 |  |  | (2,969 | )
Ending balance |  | $ | (97,226 | ) |  | $ | (88,602 | ) |  | $ | (104,739 | ) |  | $ | (6,597 | ) |  | $ | (5,409 | ) |  | $ | (8,378 | )
Weighted-Average Rate Assumptions Used | The weighted-average rate assumptions used to determine projected benefit obligations were as follows:
|  | December 31,
|  | 2018 |  | 2019
Discount rate—Salaried plan |  | 3.99% |  | 3.02%
Discount rate—USW plan |  | 3.94% |  | 2.96%
Discount rate—IUOE plan |  | 4.12% |  | 3.09%
Discount rate—Other Postretirement Benefits |  | 4.08% |  | 3.06%
Rate of compensation increase—Salaried plan |  | 6.90% |  | 4.72%
Rate of compensation increase—USW plan |  | 3.50% |  | 3.28%
Rate of compensation increase—IUOE plan |  | 5.00% |  | 4.78%
The weighted-average rate assumptions used to determine net pension and other postretirement benefit plans expense were as follows:
|  | For the Year Ended December 31,
|  | 2017 |  | 2018 |  | 2019
Discount rate—Salaried plan |  | 4.21% |  | 3.70% |  | 3.99%
Discount rate—USW plan |  | 4.04% |  | 3.63% |  | 3.73%
Discount rate—IUOE plan |  | 4.41% |  | 3.79% |  | 4.12%
Discount rate—Other Postretirement Benefits |  | 3.85% |  | 3.43% |  | 4.08%
Rate of compensation increase—Salaried plan |  | 4% - 11% |  | 6.80% |  | 6.90%
Rate of compensation increase—USW plan |  | 3.50% |  | 3.50% |  | 3.50%
Rate of compensation increase—IUOE plan |  | 5.00% |  | 5.00% |  | 5.00%
Expected rate of return on plan assets—Salaried plan |  | 6.00% |  | 6.00% |  | 4.60%
Expected rate of return on plan assets—USW plan |  | 6.00% |  | 6.00% |  | 4.60%
Expected rate of return on plan assets—IUOE plan |  | 6.00% |  | 6.00% |  | 4.70%
Schedule of Allocation of Plan Assets | The target allocation and actual weighted-average asset allocation percentages at December 31, 2018 and 2019 were as follows:
|  | 2018 |  | 2019
|  | Actual |  | Target |  | Actual |  | Target
Equity securities |  | 29% |  | 30% |  | 30% |  | 30%
Fixed income securities |  | 67% |  | 67% |  | 67% |  | 67%
Other |  | 4% |  | 3% |  | 3% |  | 3%
Fair Value, Assets Measured on Recurring Basis | The fair values of the pension plan assets at December 31, 2018 were as follows (in thousands):
Asset Category |  | Total |  | Quoted Prices in Active Markets for Identical Assets (Level 1) |  | Significant Observable Inputs (Level 2) |  | Significant Unobservable Inputs (Level 3)
Domestic Equity Securities(1): |  |  |  |  |  |  |  |
Small-cap fund |  | $ | 3,816 |  |  | $ | 3,816 |  |  | $ | — |  |  | $ | — |
Mid-cap fund |  | 3,811 |  |  | 3,811 |  |  | — |  |  | — |
Large-cap fund |  | 30,595 |  |  | 30,595 |  |  | — |  |  | — |
International equity fund |  | 19,471 |  |  | 19,471 |  |  | — |  |  | — |
Fixed Income Securities(1): |  |  |  |  |  |  |  |
Short-term bond fund |  | 9,242 |  |  | 9,242 |  |  | — |  |  | — |
Intermediate-term bond fund |  | 23,036 |  |  | 23,036 |  |  | — |  |  | — |
Long-term investment grade bond funds |  | 99,118 |  |  | 99,118 |  |  | — |  |  | — |
Other: |  |  |  |  |  |  |  |
Short-term investment fund |  | 8,312 |  |  | 8,312 |  |  | — |  |  | — |
Group annuity contract |  | 189 |  |  | — |  |  | — |  |  | 189 |
Fair value of plan assets |  | $ | 197,590 |  |  | $ | 197,401 |  |  | $ | — |  |  | $ | 189 |
(1) We hold equity and fixed income securities through investments in mutual funds, which are dedicated to each category as indicated. The fair values of the pension plan assets at December 31, 2019 were as follows (in thousands):
Asset Category |  | Total |  | Quoted Prices in Active Markets for Identical Assets (Level 1) |  | Significant Observable Inputs (Level 2) |  | Significant Unobservable Inputs (Level 3)
Domestic Equity Securities(1): |  |  |  |  |  |  |  |
Small-cap fund |  | $ | 5,087 |  |  | $ | 5,087 |  |  | $ | — |  |  | $ | — |
Mid-cap fund |  | 5,095 |  |  | 5,095 |  |  | — |  |  | — |
Large-cap fund |  | 40,884 |  |  | 40,884 |  |  | — |  |  | — |
International equity fund |  | 25,580 |  |  | 25,580 |  |  | — |  |  | — |
Fixed Income Securities(1): |  |  |  |  |  |  |  |
Short-term bond fund |  | 3,590 |  |  | 3,590 |  |  | — |  |  | — |
Intermediate-term bond fund |  | 29,485 |  |  | 29,485 |  |  | — |  |  | — |
Long-term investment grade bond funds |  | 132,096 |  |  | 132,096 |  |  | — |  |  | — |
Other: |  |  |  |  |  |  |  |
Short-term investment fund |  | 7,300 |  |  | 7,300 |  |  | — |  |  | — |
Group annuity contract |  | 176 |  |  | — |  |  | — |  |  | 176 |
Fair value of plan assets |  | $ | 249,293 |  |  | $ | 249,117 |  |  | $ | — |  |  | $ | 176 |
(1) We hold equity and fixed income securities through investments in mutual funds, which are dedicated to each category as indicated.
Expected Benefit Payments | As of December 31, 2019, the benefit amounts expected to be paid from plan assets through December 31, 2029 were as follows (in thousands):
|  | Pension Benefits |  | Other Postretirement Benefits
2020 |  | $ | 15,943 |  |  | $ | 1,163 |
2021 |  | $ | 16,473 |  |  | $ | 1,187 |
2022 |  | $ | 18,981 |  |  | $ | 1,141 |
2023 |  | $ | 21,445 |  |  | $ | 1,080 |
2024 |  | $ | 23,621 |  |  | $ | 938 |
2025 through 2029 |  | $ | 136,931 |  |  | $ | 4,069 |

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