Acquisitions and Discontinued Operations - Acquisitions (Details) - USD ($) $ in Millions			1 Months Ended	12 Months Ended
	Feb. 13, 2019	Feb. 12, 2019	Feb. 28, 2019	Dec. 31, 2018	Dec. 31, 2019	Dec. 31, 2017
Business Acquisition [Line Items]
Goodwill				$ 2,072.7	$ 2,258.3	$ 2,112.8
Useful life				11 years
Finite-lived intangible assets acquired				$ 19.1
Aquion
Business Acquisition [Line Items]
Payments to acquire businesses	$ 163.4
Goodwill			$ 87.5
Business Acquisition, Goodwill, Expected Tax Deductible Amount			4.6
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Indefinite-Lived Intangible Assets			$ 15.7
Useful life			15 years
Finite-lived intangible assets acquired			$ 78.8
Pelican
Business Acquisition [Line Items]
Payments to acquire businesses		$ 121.1
Goodwill			118.0
Business Acquisition, Goodwill, Expected Tax Deductible Amount			$ 7.6