Fair Value of Assets & Liabilities - Narrative (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
Mar. 31, 2019	Dec. 31, 2019
Segment Reporting Information [Line Items]
Gain/(loss) on instrument specific credit risk	$ 0.3
Disposition of Acquired Properties \| Corporate
Segment Reporting Information [Line Items]
Asset impairment charges		$ 4.6
Reversed asset impairment charges		0.7
Disposition of Acquired Properties \| 2019 Business Optimization \| Corporate
Segment Reporting Information [Line Items]
Asset impairment charges		1.5
Leased Assets \| 2019 Business Optimization \| Corporate
Segment Reporting Information [Line Items]
Asset impairment charges		14.0
Reversed asset impairment charges		1.4
Leased Assets \| Rebranding Initiative \| Corporate
Segment Reporting Information [Line Items]
Asset impairment charges		$ 7.1

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Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
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+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 30
-Subparagraph (c)(1)
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+ References

No definition available.

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