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Employee Benefits - Additional Information (Details) - USD ($) | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Mar. 31, 2020 | Sep. 30, 2020 | Sep. 30, 2019 | Dec. 31, 2019
Defined Benefit Plan Disclosure |  |  |  |
Payment for Other Postretirement Benefits |  | $ 2,900,000 | $ 2,100,000 |
Postretirement Health Coverage | Salaried VEBA |  |  |  |
Defined Benefit Plan Disclosure |  |  |  |
Maximum contribution threshold |  | 2,900,000 |  |
Payment for Other Postretirement Benefits | $ 2,900,000 |  |  |
Level 2 | Fair Value, Measurements, Recurring |  |  |  |
Defined Benefit Plan Disclosure |  |  |  |
Fair value of deferred compensation assets |  | 9,100,000 |  | $ 8,100,000
Accrued salaries, wages and related expenses |  |  |  |
Defined Benefit Plan Disclosure |  |  |  |
Accrued salaries, wages and related expenses |  | $ 3,700,000 |  |

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- Definition Carrying value as of the balance sheet date of obligations incurred and payable for incentive compensation awarded to employees and directors or earned by them based on the terms of one or more relevant arrangements. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.15(a)) -URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.15(5)) -URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878 + Details
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- Definition Amount of cash outflow for other postretirement benefit. Includes, but is not limited to, employer contribution to fund plan asset and payment to retiree. Excludes pension benefit. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 25 -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3536-108585 + Details
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