Effective Income Tax Rate Reconciliation, Foreign Tax Reform, Amount

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Income Tax Reconciliation Unrecognized Tax Benefits Reductions Resulting From Lapse Of Applicable Statute Of Limitations

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Amount of difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying domestic federal statutory income tax rate to pretax income (loss) from continuing operation, attributable to expense for award under share-based payment arrangement. Excludes expense determined to be nondeductible upon grant or after for award under share-based payment arrangement.

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Amount 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 increase (decrease) in the income tax rates.

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Amount of the difference between reported income tax expense (benefit) and the expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to deduction for qualified production activity.

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Amount 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 foreign income tax expense (benefit).

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The amount of income tax expense or benefit for the period computed by applying the domestic federal statutory tax rates to pretax income from continuing operations.

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Amount of reported income tax expense (benefit) in excess of (less than) expected income tax expense (benefit) computed by applying domestic federal statutory income tax rate to pretax income (loss) from continuing operation, attributable to nondeductible expense for award under share-based payment arrangement. Includes, but is not limited to, expense determined to be nondeductible upon grant or after for award under share-based payment arrangement.

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Amount 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 state and local income tax expense (benefit).

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Income Taxes - Schedule Of Income Tax Difference From Statutory Rate (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended								12 Months Ended
	Aug. 31, 2019	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Federal tax at statutory rate										$ 315.5	$ 268.7	$ 386.7
State taxes, net of federal benefits										29.7	20.8	16.0
Foreign rate differential										(56.2)	(44.7)	(115.7)
U.S. tax on foreign earnings										55.0	43.7	8.4
Research and development credit										(32.7)	(25.2)	(15.3)
Share-based compensation not benefited										13.5	9.9	10.8
Domestic production activities deduction										0.0	0.0	(7.9)
Reversal of unrecognized tax benefits										(8.4)	(5.2)	(62.4)
Tax Cuts and Jobs Act impact										0.0	0.5	317.8
Excess tax benefits related to share-based compensation arrangements		$ (33.7)	$ (28.8)	$ (11.3)	$ (72.7)	$ (15.8)	$ (24.1)	$ (21.6)	$ (54.7)	(146.5)	(116.2)	(102.8)
Deferred tax remeasurement due to Swiss Tax Reform	$ (51.3)									(51.3)	0.0	0.0
Other										1.8	2.2	(1.7)
Total income tax expense										$ 120.4	$ 154.5	$ 433.9