Effective Income Tax Rate Reconciliation, Intangible Asset Impairment, Percent

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[Line Items] for Schedule Of Asset Acquisition, By Acquisition [Table]

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Amount of deferred income tax expense (benefit) pertaining to income (loss) from continuing operations.

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to deductions. Including, but not limited to, extraterritorial income exclusion deduction, qualified production activity deduction, dividend deduction, deduction for dividend paid to employee stock ownership plan, Medicare prescription drug benefit subsidy deduction, and other deductions.

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Amount of impairment loss resulting from write-down of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit to fair value.

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Income Taxes (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
Income Taxes (Narrative) (Details) - USD ($) $ in Millions	Jun. 30, 2020	Mar. 31, 2019	Jun. 30, 2020	Jun. 30, 2019
Schedule Of Asset Acquisition, By Acquisition [Line Items]
Effective Income Tax Rate Reconciliation, Intangible Asset Impairment, Percent			11.10%
Effective Income Tax Rate Reconciliation, Deduction, Percent				12.10%
Purchased technology
Schedule Of Asset Acquisition, By Acquisition [Line Items]
Impairment	$ 2,042.3
Intangible Asset Impairment
Schedule Of Asset Acquisition, By Acquisition [Line Items]
Deferred Income Tax Expense (Benefit)	$ (377.3)
Intellectual Property Election
Schedule Of Asset Acquisition, By Acquisition [Line Items]
Deferred Income Tax Expense (Benefit)		$ (95.7)
Valuation Allowance Release
Schedule Of Asset Acquisition, By Acquisition [Line Items]
Deferred Income Tax Expense (Benefit)		$ (30.3)