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Leases - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Jan. 01, 2019
Segment Reporting Information [Line Items]
Operating lease assets	$ 209.9	$ 220.1
Operating liabilities	229.1
Right-of-use asset impairment charge	2.0	1.4
ASU 2016-02
Segment Reporting Information [Line Items]
Operating lease assets			$ 222.6
Operating liabilities			236.7
ASU 2016-02 | Retained Earnings
Segment Reporting Information [Line Items]
Cumulative effect adjustments to retained earnings			$ 6.1
U.K.
Segment Reporting Information [Line Items]
Operating lease assets	89.6	100.1
Right-of-use asset impairment charge	1.8	1.4
Brazil
Segment Reporting Information [Line Items]
Operating lease assets	2.8	$ 5.2
Right-of-use asset impairment charge	$ 0.2

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- Definition

Amount of loss from impairment of right-of-use asset from operating lease.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 25
-Paragraph 6
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=77888369&loc=SL77918431-209957

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- Definition

Present value of lessee's discounted obligation for lease payments from operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918627-209977

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Amount of lessee's right to use underlying asset under operating lease.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (a)
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