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v3.20.4

Other Expense, Net (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Other Income And Expenses [Abstract] |  |  |
Interest income | $ 0.6 | $ 0.6 | $ 0.3
Net periodic postretirement benefit cost relating to Salaried VEBA | (4.7) | (6.5) | (6.0)
Realized gain on available for sale securities | 2.0 | 4.4 | 5.4
Unrealized gain (loss) on equity securities | 0.7 | 0.7 | (1.0)
Loss on extinguishment of debt |  | (20.3) |
All other, net |  | 0.4 | 0.4
Other expense, net | $ (1.4) | $ (20.7) | $ (0.9)

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- Definition Amount of realized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 9 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=121645371&loc=d3e27357-111563 + Details
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