Share-Based Compensation (Narrative) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2020	Mar. 31, 2020	Jun. 30, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized, Share-based Awards Other than Options	$ 215		$ 215
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized, Stock Options	67		67
Stock Repurchase Program, Authorized Amount	3,700		3,700
Stock Repurchase Program, Remaining Authorized Repurchase Amount	$ 1,030		$ 1,030
Dividends Payable, Date Declared	May 21, 2020	Mar. 19, 2020
Dividends Payable, Amount Per Share	$ 0.18	$ 0.18	$ 0.18
Dividends Payable, Date to be Paid	Jul. 17, 2020	Apr. 17, 2020
Dividends Payable, Date of Record	Jun. 05, 2020	Apr. 03, 2020
Dividends Payable	$ 56		$ 56
Treasury Stock, Value, Acquired, Cost Method			$ 650
Treasury Stock, Shares, Acquired			9,200
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Period of recognition for remaining share-based compensation expense			2 years 3 months 25 days
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Period of recognition for remaining share-based compensation expense			2 years 3 months 25 days

Date the declared dividend will be paid, in CCYY-MM-DD format.

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The per share amount of a dividend declared, but not paid, as of the financial reporting date.

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Carrying value as of the balance sheet date of dividends declared but unpaid on equity securities issued by the entity and outstanding.

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Date the dividend to be paid was declared, in CCYY-MM-DD format.

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Date the holder must own the stock to be entitled to the dividend, in CCYY-MM-DD format.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

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Amount of cost to be recognized for option under share-based payment arrangement.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of stock repurchase plan authorized.

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Amount remaining of a stock repurchase plan authorized.

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Number of shares that have been repurchased during the period and are being held in treasury.

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Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method.

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