Business Acquisitions - Finite-Lived and Indefinite-Lived Intangible Assets Acquired as Part of Business Combination (Details) - Conwed $ in Millions	Jan. 20, 2017 USD ($)
Finite-Lived and Indefinite-Lived Intangible Assets Acquired as Part of Business Combination [Line Items]
Fair Value	$ 134.4
Trade names
Finite-Lived and Indefinite-Lived Intangible Assets Acquired as Part of Business Combination [Line Items]
Fair Value	7.1
Total amortizable intangible assets
Finite-Lived and Indefinite-Lived Intangible Assets Acquired as Part of Business Combination [Line Items]
Fair Value	127.3
Customer relationships
Finite-Lived and Indefinite-Lived Intangible Assets Acquired as Part of Business Combination [Line Items]
Fair Value	$ 108.0
Weighted-Average Amortization Period (Years)	15 years
Developed technology
Finite-Lived and Indefinite-Lived Intangible Assets Acquired as Part of Business Combination [Line Items]
Fair Value	$ 18.1
Weighted-Average Amortization Period (Years)	17 years 2 months 12 days
Non-competition agreements
Finite-Lived and Indefinite-Lived Intangible Assets Acquired as Part of Business Combination [Line Items]
Fair Value	$ 1.2
Weighted-Average Amortization Period (Years)	7 years 2 months 12 days

[Line Items] for Finite-Lived and Indefinite-Lived Intangible Assets Acquired as Part of Business Combination [Table]

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- Definition

Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16265-109275

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- Definition

Amount of intangible assets, excluding goodwill, acquired at the acquisition date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=116869197&loc=d3e4845-128472

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