Income Taxes [Line Items]

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- Definition

One time transition tax on deferred foreign income, cash and other net current assets.

+ References

No definition available.

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- Definition

One time transition tax on deferred foreign income, remaining.

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- Definition

Carrying amount as of the balance sheet date of the unpaid sum of the known and estimated amounts payable to satisfy all domestic and foreign income tax obligations due beyond one year or the operating cycle, whichever is longer. Alternate captions include income taxes payable, noncurrent.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

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

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-Publisher FASB
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- Definition

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

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- Definition

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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Income Taxes - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended			12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Jun. 30, 2018	Dec. 31, 2017	Dec. 31, 2016	Jun. 30, 2018	Sep. 30, 2017	Jun. 30, 2017
Income Taxes [Line Items]
Effective tax rate	169.00%	22.00%		98.00%	20.00%
U.S. federal statutory tax rate				35.00%
Provision for income taxes	$ 15,471	$ 1,755		$ 16,879	$ 2,915
Long-term income taxes	30,050			$ 30,050			$ 13,944	$ 13,485
Forecast
Income Taxes [Line Items]
U.S. federal statutory tax rate			21.00%			28.00%
Tax Cuts and Jobs Act
Income Taxes [Line Items]
One-time transition tax on deferred foreign income, cash and other net current assets				15.50%
One-time transition tax on deferred foreign income, remaining				8.00%
Provision for income taxes	13,800
Charge related to transition tax	17,800
Benefit from impact of changes in tax rate	4,000
Benefit of deferred taxes related to GILTI	454
Tax Contingencies and Other Income Tax Liabilities
Income Taxes [Line Items]
Long-term income taxes	$ 13,800			$ 13,800				$ 13,500