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v3.20.2

Components of Retirement Plan Costs (Detail) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2020 | Jun. 30, 2019 | Jun. 30, 2020 | Jun. 30, 2019
Pension Plans |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Service Cost | $ 831 | $ 776 | $ 1,662 | $ 1,552
Interest Cost | 1,443 | 1,621 | 2,887 | 3,242
Expected Return on Plan Assets | (2,255) | (2,118) | (4,510) | (4,237)
Prior Service Cost Amortization | 80 | 80 | 160 | 160
Actuarial Loss Amortization | 1,618 | 1,081 | 3,236 | 2,162
Sub-total | 1,717 | 1,440 | 3,435 | 2,879
Amounts Capitalized and Deferred | (807) | (597) | (1,437) | (1,009)
Net Periodic Benefit Cost Recognized | 910 | 843 | 1,998 | 1,870
Other Postretirement Benefit Plans, Defined Benefit |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Service Cost | 675 | 576 | 1,350 | 1,152
Interest Cost | 779 | 856 | 1,559 | 1,712
Expected Return on Plan Assets | (516) | (411) | (1,032) | (822)
Prior Service Cost Amortization | 303 | 303 | 606 | 606
Actuarial Loss Amortization | 186 | 57 | 372 | 114
Sub-total | 1,427 | 1,381 | 2,855 | 2,762
Amounts Capitalized and Deferred | (695) | (606) | (1,227) | (1,080)
Net Periodic Benefit Cost Recognized | 732 | 775 | 1,628 | 1,682
Supplemental Employee Retirement Plans, Defined Benefit |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Service Cost | 71 | 63 | 142 | 123
Interest Cost | 138 | 145 | 275 | 284
Prior Service Cost Amortization | 14 | 25 | 28 | 28
Actuarial Loss Amortization | 259 | 156 | 518 | 314
Sub-total | 482 | 389 | 963 | 749
Amounts Capitalized and Deferred | (152) | (112) | (290) | (215)
Net Periodic Benefit Cost Recognized | $ 330 | $ 277 | $ 673 | $ 534

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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 http://asc.fasb.org/extlink&oid=118257860&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 http://asc.fasb.org/extlink&oid=118255775&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 http://asc.fasb.org/extlink&oid=109237824&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 http://asc.fasb.org/extlink&oid=118257860&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 http://asc.fasb.org/extlink&oid=118255775&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 http://asc.fasb.org/extlink&oid=118257860&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 http://asc.fasb.org/extlink&oid=118257860&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 http://asc.fasb.org/extlink&oid=118255775&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 http://asc.fasb.org/extlink&oid=109237824&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 http://asc.fasb.org/extlink&oid=118255775&loc=d3e2709-114920 + Details
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