v3.20.1

Employee Benefit Plans (Narrative) (Details) $ in Thousands | 12 Months Ended |
--- | --- | ---
Dec. 31, 2019 USD ($) pension_plan | Dec. 31, 2018 USD ($) | Dec. 31, 2017 USD ($) | Dec. 31, 2016 USD ($)
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Defined contribution plan, expenses | $ 11,400 | $ 11,000 | $ 9,900 |
Number of Union Pension Plans | pension_plan | 2 |  |  |
Long-term pension and benefits | $ 145,992 | 122,580 |  |
Accumulated other comprehensive loss | $ (162,077) | $ (120,491) |  |
Defined Benefit Plan, Health Care Cost Trend Rate Assumed, Next Fiscal Year | 6.00% |  |  |
Defined Benefit Plan, Ultimate Health Care Cost Trend Rate | 5.08% |  |  |
Fixed Income Securities [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 67.00% | 67.00% |  |
Fixed Income Securities [Member] | Scenario, Plan [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 70.00% |  |  |
Equity Securities [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 30.00% | 30.00% |  |
Equity Securities [Member] | Scenario, Plan [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 30.00% |  |  |
Pension Plan [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Defined Benefit Plan, Benefit Obligation, Actuarial Gain (Loss) | $ (54,171) | $ 21,375 |  |
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) | 36,082 | 52,530 | 27,997 |
Long-term pension and benefits | 131,947 | 111,359 |  |
Accumulated other comprehensive loss | (104,739) | (88,602) | (97,226) | $ (58,584)
Defined Benefit Plan, Expected Amortization of Gain (Loss), Next Fiscal Year | (5,700) |  |  |
Defined Benefit Plan, Expected Amortization of Prior Service Cost (Credit), Next Fiscal Year | (200) |  |  |
Contributions estimated to be paid | 31,300 |  |  |
Other Postretirement Benefits [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Defined Benefit Plan, Benefit Obligation, Actuarial Gain (Loss) | (3,300) | 599 |  |
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) | 1,031 | 1,248 | 1,467 |
Long-term pension and benefits | 14,045 | 11,221 |  |
Accumulated other comprehensive loss | (8,378) | (5,409) | $ (6,597) | $ (7,881)
Defined Benefit Plan, Expected Amortization of Gain (Loss), Next Fiscal Year | (500) |  |  |
Contributions estimated to be paid | $ 1,200 |  |  |
Error in Actuarial Assumptions [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) |  | 19,400 |  |
Long-term pension and benefits |  | 22,200 |  |
Accumulated other comprehensive loss |  | $ (2,800) |  |

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- Definition Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=118930883&loc=d3e637-108580 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 14A -URI http://asc.fasb.org/extlink&oid=118930883&loc=SL7669686-108580 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 14 -URI http://asc.fasb.org/extlink&oid=118930883&loc=d3e681-108580 + Details
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- Definition Assumed rate, for next fiscal year, based on annual change in cost of health care cost benefits used to measure expected cost of benefits covered by defined benefit postretirement plan. Factors include, but are not limited to, estimate of health care inflation, change in health care utilization or delivery pattern, technological advances, and change in health status of participant. Excludes factors for change in composition of plan population by age and dependency status. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (l) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 + Details
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