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Share-Based Payments and Long-term Incentive Plan - Narrative (Details) - USD ($) $ / shares in Units, $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2019 | Mar. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Business acquisition, share price |  | $ 42.75
Share-based payment and LTIP expense | $ 3.5 |
Allocated share-based compensation expense | 21.6 |
Allocated share-based compensation expense offset | 21.6 |
Other share-based arrangements, expense | 1.9 |
Income tax benefit | 0.3 |
Performance Shares |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Allocated share-based compensation expense | 0.8 |
Deferred cash awards |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Allocated share-based compensation expense | $ 0.8 |

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