Discontinued business operation accumulated other comprehensive income loss tax.

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Equity Method Investment, Sales Reported on Consolidated Financial Statements.

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Indefinite-lived intangible assets useful life description.

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Percentage of difference in carrying value of investment recorded in discontinued operation.

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Share in equity method investee gain loss on sale.

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Difference between amount at which an investment accounted for under the equity method of accounting is carried (reported) on the balance sheet and amount of underlying equity in net assets the reporting Entity has in the investee.

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount of gain (loss) from sale and disposal of integrated set of activities and assets capable of being conducted and managed for purpose of providing return in form of dividend, lower cost, or other economic benefit to investor, owner, member and participant.

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The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of an intangible asset (excluding goodwill) to fair value.

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Amount of income (loss) for proportionate share of equity method investee's income (loss).

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Amount of distribution received from equity method investee for return of investment, classified as investing activities. Excludes distribution for return on investment, classified as operating activities.

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Equity Investments (Narrative) (Details) - USD ($)	3 Months Ended	12 Months Ended
Equity Investments (Narrative) (Details) - USD ($)	Sep. 30, 2019	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Schedule of Equity Method Investments [Line Items]
Distributions from equity interest		$ 85,200,000	$ 141,700,000	$ 69,100,000
Equity method investment, sales reported on consolidated financial statements		33,500,000	32,800,000	31,200,000
Equity earnings in joint venture		96,600,000	74,900,000	67,000,000.0
Share in equity method investee gain on sale		20,600,000
Write-off		$ 0	0	0
Developed Technology [Member]
Schedule of Equity Method Investments [Line Items]
Amortizing intangible assets, Estimated Useful Life		15 years
WAVE [Member]
Schedule of Equity Method Investments [Line Items]
Equity interest percentage	50.00%	50.00%
Distributions from equity interest		$ 85,200,000	141,700,000	69,100,000
Percentage of difference in carrying value of investment recorded in discontinued operation		50.00%
Equity method investment, difference between carrying amount and underlying equity		$ 145,800,000	155,500,000
WAVE [Member] \| Customer Relationships [Member]
Schedule of Equity Method Investments [Line Items]
Amortizing intangible assets, Estimated Useful Life		20 years
WAVE [Member] \| Developed Technology [Member]
Schedule of Equity Method Investments [Line Items]
Amortizing intangible assets, Estimated Useful Life		15 years
WAVE [Member] \| Customer Relationships and Developed Technology Assets [Member]
Schedule of Equity Method Investments [Line Items]
Write-off	$ 4,400,000
WAVE [Member] \| Trademarks [Member]
Schedule of Equity Method Investments [Line Items]
Non-amortizing intangible assets, estimated useful life		indefinite
WAVE [Member] \| WAVE’s European and Pacific Rim businesses [Member]
Schedule of Equity Method Investments [Line Items]
Gain on sale of businesses		$ 46,200,000
WAVE [Member] \| WAVE’s European and Pacific Rim businesses [Member] \| Foreign Currency Translation Adjustments [Member]
Schedule of Equity Method Investments [Line Items]
(Loss) gain due to change in carrying value of discontinued operations net assets		10,200,000
WAVE [Member] \| European And Pacific Rim Businesses
Schedule of Equity Method Investments [Line Items]
Equity earnings in joint venture		$ 3,000,000.0	$ 1,500,000	$ 1,700,000