Income Taxes - Tax Effects Of Temporary Differences (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Income Tax Disclosure [Abstract]
NOL and tax credit carryforwards	$ 471.6	$ 612.9
163 (j) interest expense carryforward	65.7	49.3
Lease liabilities	32.5	22.1
ROU asset	(32.5)	(22.1)
Tax-deductible goodwill and amortizable intangibles	(38.0)	(48.6)
Capitalization of research and development expenses	90.7	42.7
Reserves and accruals	68.4	27.5
Property, plant and equipment	(95.8)	(81.2)
Inventories	84.3	22.0
Undistributed earnings of foreign subsidiaries	(57.5)	(63.7)
Share-based compensation	7.7	10.3
Pension	21.2	26.3
Other	3.2	8.0
Deferred tax assets and liabilities before valuation allowance	621.5	605.5
Valuation allowance	(249.9)	(357.9)
Net deferred tax asset	$ 371.6	$ 247.6

Deferred Tax Asset, Lease Liabilities

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Deferred tax assets (liabilities), gross

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Deferred tax assets operating loss and tax credit carryforwards

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Amount, before allocation of valuation allowance, of deferred tax asset attributable to deductible interest carryforward.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from in-process research and development costs expensed in connection with a business combination.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from inventory.

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Amount, after allocation of valuation allowances and deferred tax liability, of deferred tax asset attributable to deductible differences and carryforwards, without jurisdictional netting.

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Amount, before allocation of valuation allowance, of deferred tax asset attributable to deductible temporary differences, classified as other.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from pension benefits.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from share-based compensation.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from reserves and accruals.

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Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

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Amount of deferred tax liability attributable to taxable temporary differences from intangible assets including goodwill.

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Amount of deferred tax liability attributable to taxable temporary differences from leasing arrangements.

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Amount of deferred tax liability attributable to taxable temporary differences from property, plant, and equipment.

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Amount of deferred tax liability attributable to taxable temporary differences from undistributed earnings of subsidiary and other recognized entity not within country of domicile. Includes, but is not limited to, other basis differences.

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