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Fair Value of Assets & Liabilities - Narrative (Details) - Corporate $ in Millions | 12 Months Ended
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Dec. 31, 2019 USD ($)
Disposition of Acquired Properties |
Segment Reporting Information [Line Items] |
Asset impairment charges | $ 4.6
Reversed asset impairment charges | 0.7
Disposition of Acquired Properties | 2019 Business Optimization |
Segment Reporting Information [Line Items] |
Asset impairment charges | 1.5
Leased Assets | 2019 Business Optimization |
Segment Reporting Information [Line Items] |
Asset impairment charges | 14.0
Reversed asset impairment charges | 1.4
Leased Assets | Rebranding Initiative |
Segment Reporting Information [Line Items] |
Asset impairment charges | $ 7.1

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