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Components of Retirement Plan Costs (Detail) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2022 | Jun. 30, 2021 | Jun. 30, 2022 | Jun. 30, 2021
Pension Plans |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Service Cost | $ 791 | $ 868 | $ 1,582 | $ 1,736
Interest Cost | 1,371 | 1,251 | 2,742 | 2,502
Expected Return on Plan Assets | (2,720) | (2,423) | (5,440) | (4,846)
Prior Service Cost Amortization | 89 | 75 | 178 | 150
Actuarial Loss Amortization | 1,377 | 2,022 | 2,754 | 4,044
Sub-total | 908 | 1,793 | 1,816 | 3,586
Amounts Capitalized and Deferred | (309) | (887) | (464) | (1,600)
Net Periodic Benefit Cost Recognized | 599 | 906 | 1,352 | 1,986
Other Postretirement Benefit Plans, Defined Benefit |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Service Cost | 722 | 758 | 1,444 | 1,516
Interest Cost | 799 | 685 | 1,598 | 1,370
Expected Return on Plan Assets | (854) | (627) | (1,708) | (1,254)
Prior Service Cost Amortization | 273 | 302 | 546 | 604
Actuarial Loss Amortization | 255 | 262 | 510 | 524
Sub-total | 1,195 | 1,380 | 2,390 | 2,760
Amounts Capitalized and Deferred | (622) | (791) | (1,133) | (1,454)
Net Periodic Benefit Cost Recognized | 573 | 589 | 1,257 | 1,306
Supplemental Employee Retirement Plans, Defined Benefit |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Service Cost | 68 | 88 | 136 | 177
Interest Cost | 118 | 115 | 236 | 229
Prior Service Cost Amortization | 14 | 14 | 28 | 28
Actuarial Loss Amortization | 199 | 373 | 399 | 745
Sub-total | 399 | 590 | 799 | 1,179
Amounts Capitalized and Deferred | (119) | (178) | (238) | (356)
Net Periodic Benefit Cost Recognized | $ 280 | $ 412 | $ 561 | $ 823

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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 -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 55 -Paragraph 17 -URI https://asc.fasb.org/extlink&oid=123450688&loc=d3e4179-114921 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h)(5) -URI https://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 45 -Paragraph 3A -Subparagraph (b) -URI https://asc.fasb.org/extlink&oid=123453770&loc=SL108413299-114919 Reference 4: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 55 -Paragraph 18 -URI https://asc.fasb.org/extlink&oid=123450688&loc=d3e4587-114921 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 6 -Subparagraph (a)(5) -URI https://asc.fasb.org/extlink&oid=123447040&loc=d3e2709-114920 + 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 -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 55 -Paragraph 17 -URI https://asc.fasb.org/extlink&oid=123450688&loc=d3e4179-114921 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 55 -Paragraph 18 -URI https://asc.fasb.org/extlink&oid=123450688&loc=d3e4587-114921 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h)(3) -URI https://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 45 -Paragraph 3A -Subparagraph (b) -URI https://asc.fasb.org/extlink&oid=123453770&loc=SL108413299-114919 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 6 -Subparagraph (a)(3) -URI https://asc.fasb.org/extlink&oid=123447040&loc=d3e2709-114920 + Details
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