v3.20.2

Employee Benefit Plans (Narrative) (Details) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2020 USD ($) pension_plan | Sep. 30, 2019 USD ($) | Sep. 30, 2020 USD ($) pension_plan | Sep. 30, 2019 USD ($)
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |
Defined Contribution Plan, Cost | $ | $ 2.8 | $ 2.8 | $ 9.7 | $ 9.3
Number Of Sponsored Pension Plans | pension_plan | 2 |  | 2 |
Number Of Sponsored Pension Plans, Non-Union Employees | pension_plan | 1 |  | 1 |
Number Of Sponsored Pension Plans, Union Employees | pension_plan | 1 |  | 1 |
Pension Plan [Member] |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |
Defined Benefit Plan, Expected Future Employer Contributions, Next Fiscal Year | $ | $ 29.3 |  | $ 29.3 |
Other Postretirement Benefits Plan [Member] |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |
Defined Benefit Plan, Expected Future Employer Contributions, Next Fiscal Year | $ | $ 0.9 |  | $ 0.9 |

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- Definition Number Of Sponsored Pension Plans, Non-Union Employees + References No definition available. + Details
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- Definition Amount of contribution expected to be received by defined benefit plan from employer in next fiscal year following current fiscal year. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 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 + Details
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- Definition Amount of cost for defined contribution plan. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 70 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=49170846&loc=d3e28014-114942 + Details
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