Summary of Significant Accounting Policies Summary of Significant Accounting Policies (Investment in Unconsolidated Affiliates) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Schedule of Equity Method Investments [Line Items]
Proceeds from sale of unconsolidated affiliates	$ 5.0	$ 9.9	$ 0.0
Gain on sale of unconsolidated affiliates	1.2	0.2	0.0
Gain from unconsolidated affiliates	3.8	(3.7)	0.0
Loss on impairment and disposal of assets	37.0	0.0	$ 207.3
Investment in Unconsolidated Affiliates, Other than Temporary Impairment		$ 0.0
Biosyn Holdings, LLC
Schedule of Equity Method Investments [Line Items]
Proceeds from sale of unconsolidated affiliates	5.0
Fluid Holding Corp
Schedule of Equity Method Investments [Line Items]
Loss on impairment and disposal of assets	$ 25.4

Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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This item represents an other than temporary decline in value that has been recognized against an investment accounted for under the equity method of accounting. The excess of the carrying amount over the fair value of the investment represents the amount of the write down which is or was reflected in earnings. The written down value is a new cost basis with the adjusted value of the investment becoming its new carrying value subject to the equity accounting method. Evidence of a loss in value might include, but would not necessarily be limited to, absence of an ability to recover the carrying amount of the investment or inability of the investee to sustain an earnings capacity which would justify the carrying amount of the investment.

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Amount of gain (loss) on sale or disposal of an equity method investment.

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This element represents the undistributed income (or loss) of equity method investments, net of dividends or other distributions received from unconsolidated subsidiaries, certain corporate joint ventures, and certain noncontrolled corporations; such investments are accounted for under the equity method of accounting. This element excludes distributions that constitute a return of investment, which are classified as investing activities.

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The cash inflow associated with the sale of equity method investments, which are investments in joint ventures and entities in which the entity has an equity ownership interest normally of 20 to 50 percent and exercises significant influence.

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