Goodwill (Details) $ in Millions	9 Months Ended
Sep. 30, 2019 USD ($)
Changes in carrying amounts of goodwill
Beginning balance	$ 585.5
Foreign currency translation	0.1
Purchase price adjustments	0.1
Ending balance	585.7
Segment One
Changes in carrying amounts of goodwill
Beginning balance	368.7
Foreign currency translation	0.1
Purchase price adjustments	0.0
Ending balance	368.8
Segment Two
Changes in carrying amounts of goodwill
Beginning balance	216.8
Foreign currency translation	0.0
Purchase price adjustments	0.1
Ending balance	$ 216.9

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
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-URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975

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Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Topic 350
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-Section 50
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Amount of increase (decrease) from adjustments after acquisition date under purchase accounting of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 25
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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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