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v3.23.2

Components of Retirement Plan Costs (Detail) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2023 | Jun. 30, 2022 | Jun. 30, 2023 | Jun. 30, 2022
Pension Plan [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Service Cost | $ 523 | $ 791 | $ 1,046 | $ 1,582
Interest Cost | 1,870 | 1,371 | 3,740 | 2,742
Expected Return on Plan Assets | (2,672) | (2,720) | (5,344) | (5,440)
Prior Service Cost Amortization | 88 | 89 | 177 | 178
Actuarial Loss Amortization |  | 1,377 |  | 2,754
Sub-total | (191) | 908 | (381) | 1,816
Amounts Capitalized and Deferred | 366 | (309) | 864 | (464)
Net Periodic Benefit Cost Recognized | 175 | 599 | 483 | 1,352
Other Postretirement Benefits Plan [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Service Cost | 373 | 722 | 746 | 1,444
Interest Cost | 725 | 799 | 1,450 | 1,598
Expected Return on Plan Assets | (852) | (854) | (1,704) | (1,708)
Prior Service Cost Amortization | 199 | 273 | 397 | 546
Actuarial Loss Amortization | (366) | 255 | (732) | 510
Sub-total | 79 | 1,195 | 157 | 2,390
Amounts Capitalized and Deferred | 112 | (622) | 333 | (1,133)
Net Periodic Benefit Cost Recognized | 191 | 573 | 490 | 1,257
Supplemental Employee Retirement Plan [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Service Cost | 63 | 68 | 125 | 136
Interest Cost | 188 | 118 | 377 | 236
Prior Service Cost Amortization | 14 | 14 | 28 | 28
Actuarial Loss Amortization |  | 199 |  | 399
Sub-total | 265 | 399 | 530 | 799
Amounts Capitalized and Deferred | (82) | (119) | (164) | (238)
Net Periodic Benefit Cost Recognized | $ 183 | $ 280 | $ 366 | $ 561

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- Definition Amount of prior service cost (credit) recognized in net periodic benefit cost (credit) of defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 17 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480482/715-20-55-17 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 45 -Paragraph 3A -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480535/715-20-45-3A Reference 3: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 18 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480482/715-20-55-18 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (h)(5) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Subparagraph (a)(5) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-6 + Details
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- Definition Amount of expected return (loss) recognized in net periodic benefit (cost) credit, calculated based on expected long-term rate of return and market-related value of plan assets of defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 17 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480482/715-20-55-17 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 45 -Paragraph 3A -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480535/715-20-45-3A Reference 3: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 18 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480482/715-20-55-18 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (h)(3) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Subparagraph (a)(3) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-6 + Details
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