| **Share-Based Associate Compensation Plans (Narrative) (Details) $ in Millions**                                                                   | 12 Months Ended           |
|----------------------------------------------------------------------------------------------------------------------------------------------------|---------------------------|
||
| **Share-based Compensation Arrangement by Share-based Payment Award [Line Items]**                                                                 |                      |   |   |
| Number of peers exceeded | peers_exceeded                                                                                                          | 4                         | 5 | 5 |
| Number of peers in peer group | Peers                                                                                                              | 9                         | 9 | 9 |
| Number of equity compensation plans | compensation_plans                                                                                           | 4                         |   |   |
| Share based compensation                                                                                                                           | $ 23                      | $ 17 | $ 15 |
| Tax benefit from compensation expense                                                                                                              | 5                         | 9 | 8 |
| Options exercised, intrinsic value                                                                                                                 | 15                        | 19 | 25 |
| Options vested, intrinsic value                                                                                                                    | 6                         | 8 | 11 |
| Unrecognized compensation costs related to non-vested awards                                                                                       | $ 30                      |   |   |
| Expected weighted-average period to recognize the unrecognized compensation costs related to non-vested awards                                     | 1 year 8 months           |   |   |
| Maximum number of shares awarded to each full-time employee for their service | shares                                                             | 10                        |   |   |
| Proceeds from stock options exercised                                                                                                              | $ 9                       | 13 | 21 |
| Shares of common stock granted in period (in shares) | shares                                                                                      | 757,000                   |   |   |
| Stock Options                                                                                                                                      |                      |   |   |
| **Share-based Compensation Arrangement by Share-based Payment Award [Line Items]**                                                                 |                      |   |   |
| Awards exercise peirod                                                                                                                             | 10 years                  |   |   |
| Awards vesting period                                                                                                                              | 3 years                   |   |   |
| Proceeds from stock options exercised                                                                                                              | $ 9                       | $ 13 | $ 21 |
| Shares repurchased | shares                                                                                                                        | 69,649                    | 96,030 | 186,097 |
| Shares repurchased, value                                                                                                                          | $ 5                       | $ 7 | $ 13 |
| Weighted average remaining contractual term                                                                                                        | 8 years 7 months 15 days  |   |   |
| Shares authorized to be granted under the shareholder-approved plans | shares                                                                      | 17,300,000                |   |   |
| Shares available for future issuance under the plans | shares                                                                                      | 9,700,000                 |   |   |
| Stock Options | Directors                                                                                                                          |                      |   |   |
| **Share-based Compensation Arrangement by Share-based Payment Award [Line Items]**                                                                 |                      |   |   |
| Shares of common stock granted in period (in shares) | shares                                                                                      | 14,600                    |   |   |
| Performance Shares | Restricted Stock Units (RSUs) [Member]                                                                                        |                      |   |   |
| **Share-based Compensation Arrangement by Share-based Payment Award [Line Items]**                                                                 |                      |   |   |
| Shares, Issued | shares                                                                                                                            | 80,666                    | 87,228 |   |
| Awards vesting period                                                                                                                              | 3 years                   |   |   |
| Risk-free rates, minimum                                                                                                                           | 0.00%                     | 0.00% | 0.00% |
| Risk-free rates, maximum                                                                                                                           | 200.00%                   | 200.00% | 200.00% |
| share based performance metric for performance shares                                                                                              | 3 years                   |   |   |
| Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested In Period Intrinsic Value Aggregate | $ 6                       | $ 7 | $ 6 |
| Performance Shares | Minimum                                                                                                                       |                      |   |   |
| **Share-based Compensation Arrangement by Share-based Payment Award [Line Items]**                                                                 |                      |   |   |
| Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate                                  | 2.81%                     | 2.83% | 2.58% |
| Weighted-average expected term                                                                                                                     | 2 years 10 months 21 days | 2 years 10 months 21 days | 2 years 5 months 9 days |
| Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate                                 | 2.22%                     | 1.44% | 0.77% |
| Service Based Shares | Restricted Stock Units (RSUs) [Member]                                                                                      |                      |   |   |
| **Share-based Compensation Arrangement by Share-based Payment Award [Line Items]**                                                                 |                      |   |   |
| Awards vesting period                                                                                                                              | 3 years                   |   |   |
| Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested In Period Intrinsic Value Aggregate | $ 24                      | $ 23 | $ 23 |

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Maximum number of shares awarded to each full-time employee for their service
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Number of equity compensation plans
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Number of peers exceeded
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Number of peers in peer group
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| - Definition
Amount of difference between fair value of the underlying shares vested during the period.
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Share-based Compensation Arrangement by Share-based Payment Award, Options, Expected to Vest, Weighted Average Remaining Contractual Term
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share based performance metric for performance shares
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| - Definition
The amount of expense, net of income tax, recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.
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| - Definition
Unrecognized cost of unvested share-based compensation awards.
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|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.
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| - Definition
The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.
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| - Definition
Amount of cash inflow from exercise of stock options granted under share-based compensation arrangement.
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|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.
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| - Definition
The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.
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| - Definition
The risk-free interest rate assumption that is used in valuing an option on its own shares.
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| - Definition
The maximum risk-free interest rate assumption that is used in valuing an option on its own shares.
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The minimum risk-free interest rate assumption that is used in valuing an option on its own shares.
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| - Definition
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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| - Definition
The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).
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|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
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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| - Definition
Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.
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| - Definition
Net number of share options (or share units) granted during the period.
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| - Definition
Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.
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| - Definition
Number of shares of stock issued as of the balance sheet date, including shares that had been issued and were previously outstanding but which are now held in the treasury.
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|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.
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|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Equity impact of the value of stock that has been repurchased during the period and has not been retired and is not held in treasury. Some state laws may mandate the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.
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