Effective Income Tax Rate Reconciliation, Deduction, Foreign Derived Intangible Income

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Income Taxes [Line Items]

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Tax Cuts And Jobs Act Of 2017, Incomplete Accounting, Change In Tax Rate, Deferred Tax Asset, Provisional Income Tax Expense (Benefit)

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Tax Cuts and Jobs Act of 2017, Incomplete Accounting, Provisional Income Tax Expense (Benefit)

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Tax Cuts and Jobs Act of 2017, Incomplete Accounting, Provisional Income Tax Expense (Benefit), Effect On Earnings Per Share

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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 excess tax benefit for share-based compensation cost.

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Amount of cash outflow for realized tax benefit related to deductible compensation cost reported on the entity's tax return for equity instruments in excess of the compensation cost for those instruments recognized for financial reporting purposes.

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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 research tax credit.

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The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income, net of any cash received during the current period as refunds for the overpayment of taxes.

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Tax year that remains open to examination under enacted tax laws, in CCYY format.

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Amount of state and local current and deferred income tax expense (benefit) attributable to continuing operations.

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Amount of unrecognized tax benefits.

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Income Taxes - Additional Information (Detail) - USD ($)		3 Months Ended	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Taxes [Line Items]
Deferred tax asset, increase (decrease), amount	$ 2,000,000,000
Remeasurement of deferred tax asset		$ 2,000,000,000
Effect of change on earnings per share (in dollars per share)		$ 6.88		$ 6.77
Total net state income tax expense			$ 83,000,000	$ 103,000,000	$ 112,000,000
Recognized tax benefit for the impact of the tax credit			138,000,000	115,000,000	107,000,000
Excess tax benefits for share-based payment awards			(55,000,000)	(106,000,000)	(152,000,000)
Foreign derived intangible income deduction			61,000,000	0	0
U.S. manufacturing deduction benefit			0	7,000,000	117,000,000
Unrecognized tax benefits	$ 0	$ 0	0	0	0
Federal and foreign income tax payments made, net of refunds received			$ (41,000,000)	$ 1,100,000,000	$ 1,300,000,000
Internal Revenue Service (IRS) \| Tax Year 2017
Income Taxes [Line Items]
Tax years subject to examination			2017
Internal Revenue Service (IRS) \| Tax Year 2018
Income Taxes [Line Items]
Tax years subject to examination			2018
Accounting Standards Update 2016-09 \| Adjustments for \| Adjustments for New Accounting Principle, Early Adoption
Income Taxes [Line Items]
Excess income tax benefit from share-based compensation, operating activities			$ 61,000,000