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v3.19.2

Components of Net Periodic Benefit Cost (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2019 | Jun. 30, 2018 | Jun. 30, 2019 | Jun. 30, 2018 | Dec. 31, 2018
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |
Defined Benefits Plan Estimated Future Employer Contributions In Next Fiscal Year |  |  |  |  | $ 1,800
Post-Retirement Health Benefits [Member] |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |
Defined Benefits Plan Estimated Future Employer Contributions In Next Fiscal Year |  |  |  |  | $ 233
Service cost | $ 9 | $ 10 | $ 17 | $ 21 |
Interest cost | 36 | 33 | 73 | 65 |
Expected return on plan assets | 0 | 0 | 0 | 0 |
Defined Benefit Plan, Amortization of Prior Service Cost (Credit) | 0 | 0 | 0 | 0 |
Net amortization of net (gain) loss | (4) | 0 | (8) | 0 |
Net Periodic Benefit Cost | 41 | 43 | 82 | 86 |
Defined Benefit Plan, Plan Assets, Contributions by Employer |  |  | 126 |  |
Pension Plan [Member] |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |
Service cost | 304 | 347 | 609 | 694 |
Interest cost | 866 | 798 | 1,733 | 1,597 |
Expected return on plan assets | (896) | (991) | (1,793) | (1,981) |
Defined Benefit Plan, Amortization of Prior Service Cost (Credit) | 0 | 0 | 0 | 0 |
Net amortization of net (gain) loss | 390 | 362 | 779 | 723 |
Net Periodic Benefit Cost | $ 664 | $ 516 | 1,328 | $ 1,033 |
Defined Benefit Plan, Plan Assets, Contributions by Employer |  |  | $ 897 |  |

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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 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 contribution received by defined benefit plan from employer which increases plan assets. + 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 50 -Paragraph 1 -Subparagraph (d)(iv)(01) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 Reference 3: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(ii) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 6 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e2709-114920 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (b)(3) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 + Details
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