Stock Compensation Plans Stock Awards (Details 2) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Share-based Compensation by Share-based Payment Award
Stock plans, vesting period	3 years
Stock awards, outstanding, weighted average remaining contractual terms	10 months 24 days	9 months 18 days	1 year	1 year 3 months 18 days
Stock issued, settlement of fully vested stock awards, fair value grant date	$ 119	$ 93	$ 96
Stock Award Activity (Table)
Stock awards - outstanding at period start	796	938	1,148
Stock awards - granted	339	376	397
Stock awards - vested	(383)	(455)	(521)
Stock awards - forfeited	(51)	(63)	(86)
Stock awards - outstanding at period end	701	796	938	1,148
Stock Awards, Weighted Average Grant Date Fair Value [Table]
Weighted-average grant date fair value - outstanding at period start	$ 244	$ 192	$ 167
Weighted-average grant date fair value - granted	274	321	233
Weighted-average grant date fair value - vested	222	181	152
Weighted-average grant date fair value - forfeited	280	250	198
Weighted-average grant date fair value - outstanding at period end	$ 278	$ 244	$ 192	$ 167
Amended 2011 Plan [Domain]
Share-based Compensation by Share-based Payment Award
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant	5,100
Share-based Compensation Arrangement by Share-based Payment Award, Number of Additional Shares Authorized	2,400
2011 Long-Term Incentive Stock Plan [Member]
Share-based Compensation by Share-based Payment Award
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant	5,500

Stock Issued During Period, Fair Value Grant Date, Share-based Compensation

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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Weighted average remaining contractual term for equity-based awards excluding options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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Number of additional shares authorized for issuance under share-based payment arrangement.

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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