Deferred Tax Assets, Foreign Restructuring Charges

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Income Taxes [Line Items]

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

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible domestic operating loss carryforwards. Excludes state and local operating loss carryforwards.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible state and local operating loss carryforwards.

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Amount, before allocation of a valuation allowances, of deferred tax assets attributable to deductible tax credit carryforwards including, but not limited to, research, foreign, general business, alternative minimum tax, and other deductible tax credit carryforwards.

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Amount of unrecognized tax benefits.

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Amount accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.

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The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

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Amount of increase (decrease) in the valuation allowance for a specified deferred tax asset.

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Income Taxes - Narrative (Detail) - USD ($) $ in Thousands	12 Months Ended
Income Taxes - Narrative (Detail) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Taxes [Line Items]
Operating loss carryforward	$ 2,900,000
Tax credit carryforwards	171,856	$ 120,594
Tax credit carryforwards	1,700,000
Income tax benefit	571,402	31,948	$ (1,056)
Total unrecognized tax benefit	36,789	27,591	27,648	$ 18,440
Unrecognized tax benefits that would impact effective tax rate	6,100
Unrecognized tax benefits, income tax interest and penalties accrued	800	300
Federal
Income Taxes [Line Items]
Tax credit carryforwards	125,700
State
Income Taxes [Line Items]
Tax credit carryforwards	91,700
Foreign Tax Authority
Income Taxes [Line Items]
Valuation allowance (decrease) increase	424,400	(759,700)	$ 106,900
Increase in deferred tax assets related to foreign restructuring		$ 590,000
Revenue Commissioners, Ireland \| Foreign Tax Authority
Income Taxes [Line Items]
Income tax benefit	$ 574,200