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Employee Benefit Plans (Tables) | 9 Months Ended
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Sep. 30, 2020
Retirement Benefits [Abstract] |
Schedule of Net Benefit Costs | The components of net periodic benefit cost for the Defined Benefit Pension Plan were as follows (in thousands):
| Three Months Ended September 30, |  | Nine Months Ended September 30,
| 2020 | 2019 |  | 2020 | 2019
Service cost | $ | 1,352 |  | $ | 1,346 |  |  | $ | 4,058 |  | $ | 4,037 |
Interest cost | 3,356 |  | 4,344 |  |  | 10,069 |  | 13,031 |
Expected return on plan assets | (5,647) |  | (6,100) |  |  | (16,943) |  | (18,300) |
Prior service cost (benefit) | — |  | 6 |  |  | — |  | 19 |
Net loss (gain) | 2,093 |  | 941 |  |  | 6,279 |  | 2,822 |
Net periodic benefit cost | $ | 1,154 |  | $ | 537 |  |  | $ | 3,463 |  | $ | 1,609 |
Defined Benefit Postretirement Healthcare Plan The components of net periodic benefit cost for the Defined Benefit Postretirement Healthcare Plan were as follows (in thousands):
| Three Months Ended September 30, |  | Nine Months Ended September 30,
| 2020 | 2019 |  | 2020 | 2019
Service cost | $ | 514 |  | $ | 454 |  |  | $ | 1,542 |  | $ | 1,362 |
Interest cost | 412 |  | 560 |  |  | 1,237 |  | 1,683 |
Expected return on plan assets | (46) |  | (57) |  |  | (137) |  | (172) |
Prior service cost (benefit) | (136) |  | (99) |  |  | (410) |  | (298) |
Net loss (gain) | 5 |  | — |  |  | 15 |  | — |
Net periodic benefit cost | $ | 749 |  | $ | 858 |  |  | $ | 2,247 |  | $ | 2,575 |
Supplemental Non-qualified Defined Benefit and Defined Contribution Plans The components of net periodic benefit cost for the Supplemental Non-qualified Defined Benefit and Defined Contribution Plans were as follows (in thousands):
| Three Months Ended September 30, |  | Nine Months Ended September 30,
| 2020 | 2019 |  | 2020 | 2019
Service cost | $ | 1,035 |  | $ | 429 |  |  | $ | 1,482 |  | $ | 2,406 |
Interest cost | 274 |  | 324 |  |  | 824 |  | 972 |
Prior service cost (benefit) | 1 |  | — |  |  | 1 |  | 1 |
Net loss (gain) | 425 |  | 134 |  |  | 1,277 |  | 402 |
Net periodic benefit cost | $ | 1,735 |  | $ | 887 |  |  | $ | 3,584 |  | $ | 3,781 |
Schedule of Defined Benefit Plans Contributions | Contributions made in the first nine months of 2020 and anticipated contributions for 2020 and 2021 are as follows (in thousands):
|  | Contributions Made | Additional Contributions | Contributions
|  | Nine Months Ended September 30, 2020 | Anticipated for 2020 | Anticipated for 2021
Defined Benefit Pension Plan |  | $ | 12,700 |  | $ | — |  | $ | 12,700 |
Non-pension Defined Benefit Postretirement Healthcare Plans |  | $ | 4,006 |  | $ | 1,335 |  | $ | 5,227 |
Supplemental Non-qualified Defined Benefit and Defined Contribution Plans |  | $ | 1,065 |  | $ | 355 |  | $ | 1,964 |

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- Definition Tabular disclosure of the components of net benefit costs for pension plans and/or other employee benefit plans including service cost, interest cost, expected return on plan assets, gain (loss), prior service cost or credit, transition asset or obligation, and gain (loss) recognized due to settlements or curtailments. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 + Details
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