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v3.19.3

Components of Retirement Plan Costs (Detail) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2019 | Sep. 30, 2018 | Sep. 30, 2019 | Sep. 30, 2018
Pension Plans |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Service Cost | $ 776 | $ 848 | $ 2,328 | $ 2,544
Interest Cost | 1,621 | 1,469 | 4,863 | 4,407
Expected Return on Plan Assets | (2,119) | (1,946) | (6,356) | (5,838)
Prior Service Cost Amortization | 80 | 81 | 240 | 243
Actuarial Loss Amortization | 1,081 | 1,447 | 3,243 | 4,341
Sub-total | 1,439 | 1,899 | 4,318 | 5,697
Amounts Capitalized and Deferred | (650) | (962) | (1,659) | (2,590)
Net Periodic Benefit Cost Recognized | 789 | 937 | 2,659 | 3,107
Other Postretirement Benefit Plans, Defined Benefit |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Service Cost | 576 | 733 | 1,728 | 2,199
Interest Cost | 857 | 852 | 2,569 | 2,554
Expected Return on Plan Assets | (412) | (409) | (1,234) | (1,227)
Prior Service Cost Amortization | 304 | 327 | 910 | 981
Actuarial Loss Amortization | 56 | 346 | 170 | 1,038
Sub-total | 1,381 | 1,849 | 4,143 | 5,545
Amounts Capitalized and Deferred | (650) | (930) | (1,730) | (2,557)
Net Periodic Benefit Cost Recognized | 731 | 919 | 2,413 | 2,988
Supplemental Employee Retirement Plans, Defined Benefit |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Service Cost | 62 | 122 | 185 | 366
Interest Cost | 142 | 101 | 426 | 303
Prior Service Cost Amortization | 14 | 47 | 42 | 141
Actuarial Loss Amortization | 157 | 121 | 471 | 365
Sub-total | 375 | 391 | 1,124 | 1,175
Amounts Capitalized and Deferred | (107) | (113) | (322) | (339)
Net Periodic Benefit Cost Recognized | $ 268 | $ 278 | $ 802 | $ 836

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