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Stock-Based Compensation - Allocation of Share-based Compensation Costs (Details) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items] |  |  |
Stock compensation expense | $ 23.7 | $ 37.5 | $ 34.0
Stock option and appreciation rights |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items] |  |  |
Stock compensation expense | 5.6 | 12.5 | 10.2
Performance share units, stock-settled |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items] |  |  |
Stock compensation expense | 15.6 | 17.6 | 16.6
Performance share units, cash-settled |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items] |  |  |
Stock compensation expense | (0.1) | 1.0 | 0.4
Performance share units, dividend equivalents |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items] |  |  |
Stock compensation expense | 0.1 | 0.2 | 0.6
Employee stock purchase plan |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items] |  |  |
Stock compensation expense | 1.3 | 1.4 | 1.1
Deferred compensation plans and restricted share awards |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items] |  |  |
Stock compensation expense | $ 1.2 | $ 4.8 | $ 5.1

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- Definition Amount of expense for award under share-based payment arrangement. Excludes amount capitalized. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (h)(1)(i) -URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901 + Details
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