Income Taxes (Details) (USD $) In Millions	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010
Income Taxes Details [Abstract]
Increase to shareholders' net income for change in foreign tax practices	$ 22	$ 25
Effects of permanently investing South Korea earnings Overseas to shareholders' net income	18	15
Effects of permanently investing Hong Kong earnings Overseas to shareholders' net income	4	10
Effects of Hong Kong tax implementation		6
Unrecognized deferred tax liabilities related to investments in South Korean and Hong Kong subsidiaries	76
Decline in gross unrecognized tax benefits	144
Effect of IRS examination to shareholders' net income	24
Reduction in net unrecognized tax benefit resulting from IRS examination	11
Income tax benefit related to IRS examination	33
Pre-tax charge associated with IRS examination	9
Reduction of interest and penalties resulting from IRS examination	11
Unfavorable potential litigation decision	0
Effect of new legislation	5	8
Change in net income resulting from decline in gross unrecognized tax benefits.	$ 8

Accumulated deferred tax liability related to the permanently invested foreign earnings.

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The effect of the portion of the difference between the effective income tax rate and domestic federal statutory income tax rate attributable to nondeductible expenses under enacted tax laws, or differences in the methodologies used to determine expense amounts for financial statements prepared in accordance with generally accepted accounting principles, not otherwise listed in the existing taxonomy on shareholders' net income.

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Implementation effect of tax strategy in Hong Kong

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The related tax benefit to shareholders' net income of permanently invested Hong Kong foreign earnings

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The related tax benefit to shareholders' net income of permanently invested foreign earnings

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The related tax benefit to shareholders' net income of permanently invested South Korea foreign earnings

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The gross amount of decreases in unrecognized tax benefits resulting from settlements with taxing authorities recorded as a pre-tax charge.

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The gross amount of increases in unrecognized tax benefits resulting from settlements with taxing authorities recorded in income tax expense.

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The change in net income as a result of increases or decreases to gross unrecognized tax benefits.

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The amount of the additional liability or refund received or expected based on a final settlement with a taxing authority.

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The sum of the amounts of estimated penalties and interest recognized in the period arising from income tax examinations.

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The estimated range of reasonably possible losses resulting from an adverse position taken by a taxing authority.

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The gross amount of decreases in unrecognized tax benefits resulting from settlements with taxing authorities.

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The net amount of all increases and decreases in unrecognized tax benefits for the period.

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