| **Capital Stock - Changes in Treasury Stock (Details) - shares**                                           | 12 Months Ended |
|------------------------------------------------------------------------------------------------------------|-----------------|
||
| **Treasure Stock [Roll Forward]**                                                                          |            |   |   |
| Beginning balance (in shares)                                                                              | 21,751,232      | 16,981,147 | 16,781,000 |
| Shares purchased under our Repurchase Program (in shares)                                                  | 6,523,000       | 4,438,000 | 0 |
| Shares purchased for employee stock options, restricted stock and employee stock purchase plan (in shares) | 577,000         | 592,000 | 419,000 |
| Shares reissued for employee stock options, restricted stock and employee stock purchase plan (in shares)  | (2,379,000)     | (260,000) | (219,000) |
| Ending balance (in shares)                                                                                 | 26,471,738      | 21,751,232 | 16,981,147 |

| X                                                                                                                                                                                                                                                             |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Increase (Decrease) In Treasure Stock
+ References
No definition available.
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|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Number, after forfeiture, of shares or units issued under share-based payment arrangement. Excludes shares or units issued under employee stock ownership plan (ESOP).
+ References
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Number of treasury shares or units reissued. Excludes reissuance of shares or units in treasury for award under share-based payment arrangement.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Number of previously issued common shares repurchased by the issuing entity and held in treasury.
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|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Number of shares that have been repurchased during the period and are being held in treasury.
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