| **Stock-based Compensation Plans - Schedule of Option Exercise Prices (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions** | 12 Months Ended |        |        |        |
|-----------------------------------------------------------------------------------------------------------------------------------------------------|-----------------|--------|--------|--------|
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| **Share-based Compensation Arrangement by Share-based Payment Award [Line Items]**                                                                  |            |   |   |   |
| Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number                                                     | 2,835           | 2,886  | 3,657  | 5,000  |
| Options, Exercisable, Number                                                                                                                        | 2,695           | 2,407  | 2,637  |   |
| Exercise Price Range From $ 21.22 To $ 31.81 [Member]                                                                                               |            |   |   |   |
| **Share-based Compensation Arrangement by Share-based Payment Award [Line Items]**                                                                  |            |   |   |   |
| Exercise Price Range, Number of Outstanding Options                                                                                                 | 807             |   |   |   |
| Stock Options Weighted Average Remaining Contractual Life                                                                                           | 3.2             |   |   |   |
| Exercise Price Range, Outstanding Options, Weighted Average Exercise Price                                                                          | $ 26.67         |   |   |   |
| Options, Outstanding, Intrinsic Value                                                                                                               | $ 1             |   |   |   |
| Exercise Price Range, Number of Exercisable Options                                                                                                 | 772             |   |   |   |
| weighted average reamining contractual term                                                                                                         | 3.1             |   |   |   |
| Exercise Price Range, Exercisable Options, Weighted Average Exercise Price                                                                          | $ 27.40         |   |   |   |
| Options, Exercisable, Intrinsic Value                                                                                                               | $ 0             |   |   |   |
| Exercise Price Range From $ 32.18 To $ 40.92 [Member]                                                                                               |            |   |   |   |
| **Share-based Compensation Arrangement by Share-based Payment Award [Line Items]**                                                                  |            |   |   |   |
| Exercise Price Range, Number of Outstanding Options                                                                                                 | 1,343           |   |   |   |
| Stock Options Weighted Average Remaining Contractual Life                                                                                           | 2.4             |   |   |   |
| Exercise Price Range, Outstanding Options, Weighted Average Exercise Price                                                                          | $ 36.85         |   |   |   |
| Options, Outstanding, Intrinsic Value                                                                                                               | $ 0             |   |   |   |
| Exercise Price Range, Number of Exercisable Options                                                                                                 | 1,265           |   |   |   |
| weighted average reamining contractual term                                                                                                         | 2.2             |   |   |   |
| Exercise Price Range, Exercisable Options, Weighted Average Exercise Price                                                                          | $ 36.89         |   |   |   |
| Options, Exercisable, Intrinsic Value                                                                                                               | $ 0             |   |   |   |
| Exercise Price Range From $ 42.48 To $ 69.91 [Member]                                                                                               |            |   |   |   |
| **Share-based Compensation Arrangement by Share-based Payment Award [Line Items]**                                                                  |            |   |   |   |
| Exercise Price Range, Number of Outstanding Options                                                                                                 | 685             |   |   |   |
| Stock Options Weighted Average Remaining Contractual Life                                                                                           | 1.5             |   |   |   |
| Exercise Price Range, Outstanding Options, Weighted Average Exercise Price                                                                          | $ 57.28         |   |   |   |
| Options, Outstanding, Intrinsic Value                                                                                                               | $ 0             |   |   |   |
| Exercise Price Range, Number of Exercisable Options                                                                                                 | 658             |   |   |   |
| weighted average reamining contractual term                                                                                                         | 1.4             |   |   |   |
| Exercise Price Range, Exercisable Options, Weighted Average Exercise Price                                                                          | $ 57.83         |   |   |   |
| Options, Exercisable, Intrinsic Value                                                                                                               | $ 0             |   |   |   |

| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
shares based compensation, shares authorized under stock option plans, exercise price range, exercisable options, weighted average reamining contractual term
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                       |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Stock Options Weighted Average Remaining Contractual Life
+ References
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - 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.
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.
+ References
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.
+ References
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Number of options outstanding, including both vested and non-vested options.
+ References
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The number of shares reserved for issuance pertaining to the outstanding exercisable stock options as of the balance sheet date in the customized range of exercise prices for which the market and performance vesting condition has been satisfied.
+ References
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The number of shares reserved for issuance pertaining to the outstanding stock options as of the balance sheet date for all option plans in the customized range of exercise prices.
+ References
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.
+ References
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Weighted average exercise price as of the balance sheet date for those equity-based payment arrangements exercisable and outstanding.
+ References
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The weighted average price as of the balance sheet date at which grantees could acquire the underlying shares with respect to all outstanding stock options which are in the customized range of exercise prices.
+ References
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| X                                                                                                                                                                                                                              |
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