| **Share-Based Associate Compensation Plans (Narrative) (Details) $ in Millions**                                                                   | 12 Months Ended          |
|----------------------------------------------------------------------------------------------------------------------------------------------------|--------------------------|
||
| **Share-based Compensation Arrangement by Share-based Payment Award**                                                                              |                     |   |   |
| Number of equity compensation plans | compensation_plans                                                                                           | 3                        |   |   |
| Maximum number of shares awarded to each full-time employee for their service | shares                                                             | 10                       |   |   |
| Share based compensation cost after tax                                                                                                            | $ 32                     | $ 29 | $ 26 |
| Tax benefit from compensation expense                                                                                                              | 8                        | 7 | 6 |
| Options exercised, intrinsic value                                                                                                                 | 14                       | 21 | 24 |
| Options vested, intrinsic value                                                                                                                    | 0                        | 2 | 15 |
| Unrecognized compensation costs related to non-vested awards                                                                                       | $ 43                     |   |   |
| Expected weighted-average period to recognize the unrecognized compensation costs related to non-vested awards                                     | 1 year 9 months 18 days  |   |   |
| Proceeds from stock options exercised                                                                                                              | $ 9                      | 10 | 13 |
| Shares of common stock granted in period (in shares) | shares                                                                                      | 384,000                  |   |   |
| Stock Options                                                                                                                                      |                     |   |   |
| **Share-based Compensation Arrangement by Share-based Payment Award**                                                                              |                     |   |   |
| Awards exercise peirod                                                                                                                             | 10 years                 |   |   |
| Awards vesting period                                                                                                                              | 3 years                  |   |   |
| Proceeds from stock options exercised                                                                                                              | $ 9                      | $ 10 | $ 13 |
| Shares repurchased | shares                                                                                                                        | 72,549                   | 80,538 | 77,947 |
| Shares repurchased, value                                                                                                                          | $ 8                      | $ 10 | $ 8 |
| Weighted average remaining contractual term                                                                                                        | 8 years 5 months 12 days |   |   |
| Shares authorized to be granted under the shareholder-approved plans | shares                                                                      | 10,300,000               |   |   |
| Shares available for future issuance under the plans | shares                                                                                      | 3,600,000                |   |   |
| Stock Options | Directors                                                                                                                          |                     |   |   |
| **Share-based Compensation Arrangement by Share-based Payment Award**                                                                              |                     |   |   |
| Shares of common stock granted in period (in shares) | shares                                                                                      | 11,524                   |   |   |
| Performance Shares | Restricted Stock Units (RSUs)                                                                                                 |                     |   |   |
| **Share-based Compensation Arrangement by Share-based Payment Award**                                                                              |                     |   |   |
| Number of peers exceeded | peers_exceeded                                                                                                          | 2                        | 1 | 6 |
| Number of peers in peer group | Peers                                                                                                              | 8                        | 8 | 9 |
| Shares, Issued | shares                                                                                                                            | 0                        | 52,335 |   |
| Awards vesting period                                                                                                                              | 3 years                  | 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 | $ 11 |
| Service Based Shares | Restricted Stock Units (RSUs)                                                                                               |                     |   |   |
| **Share-based Compensation Arrangement by Share-based Payment Award**                                                                              |                     |   |   |
| 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 | $ 22                     | $ 32 | $ 26 |

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Amount of difference between fair value of the underlying shares vested during the period.
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Amount, after tax, of expense for award under share-based payment arrangement.
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| - Definition
Amount of cost not yet recognized for nonvested award under share-based payment arrangement.
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| - Definition
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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| - Definition
Amount of tax benefit for recognition of expense of award under share-based payment arrangement.
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Amount of cash inflow from exercise of option under share-based payment arrangement.
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| - Definition
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 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
Number of shares authorized for issuance under share-based payment arrangement.
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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
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.
+ References
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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.
+ References
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