Income Taxes - Undistributed Earnings and Foreign Location Information (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Taxes.
Income tax benefits attributable to reduced tax rates or exemptions in foreign locations	$ 227	$ 228	$ 142
EPS impact of reduced tax rates or exemptions in foreign locations (in dollars per diluted share)	$ 0.38	$ 0.37	$ 0.23
Undistributed earnings of non-U.S. subsidiaries	$ 12,000

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- Definition

The amount of income taxes from which a reporting entity is exempt or for which it will receive a reduction in income taxes as a result of the income tax holiday granted by the taxing jurisdiction.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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Per share amount effect of the income tax benefit resulting from the income tax holidays granted by taxing jurisdictions.

+ References

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- Definition

Amount of undistributed earnings of foreign subsidiaries intended to be permanently reinvested outside the country of domicile.

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