Goodwill (Details) $ in Millions	3 Months Ended
Mar. 31, 2019 USD ($)
Changes in carrying amounts of goodwill
December 31, 2018	$ 585.5
Foreign currency translation	0.1
Purchase price adjustments	0.1
March 31, 2019	585.7
Segment One
Changes in carrying amounts of goodwill
December 31, 2018	368.7
Foreign currency translation	0.1
Purchase price adjustments	0.0
March 31, 2019	368.8
Segment Two
Changes in carrying amounts of goodwill
December 31, 2018	216.8
Foreign currency translation	0.0
Purchase price adjustments	0.1
March 31, 2019	$ 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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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

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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
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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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