Income Taxes - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Income Tax Disclosure [Abstract]
Effective tax rate	(12.50%)	22.20%	(86.40%)	19.30%
U.S. federal statutory rate			21.00%	21.00%
Non-deductible IPR&D charge recorded			$ 4,500
Effective income tax rate excluding non-deductible IPR&D charge	24.90%		24.00%
Tax benefit related to settlements with taxing authorities				$ 119
Estimate of reasonably possible decrease in unrecognized tax benefits	$ 500		$ 500

Effective Income Tax Rate, Excluding Nondeductible Expense, Percent

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Amount of decrease reasonably possible in the next twelve months for the unrecognized tax benefit.

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

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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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 nondeductible research and development expense.

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Amount of increase (decrease) to previously recorded tax expense. Includes, but is not limited to, significant settlements of income tax disputes, and unusual tax positions or infrequent actions taken by the entity, including tax assessment reversal, and IRS tax settlement.

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