| **Capital Stock - Changes in Outstanding Common Stock (Details) - shares shares in Thousands** | 12 Months Ended |
|------------------------------------------------------------------------------------------------|-----------------|
||
| **Changes in Common Stock [Roll Forward]**                                                     |            |   |   |
| Outstanding, beginning of year (in shares)                                                     | 111,452         | 109,331 | 107,588 |
| Shares issued for exercise of options (in shares)                                              | 0               | 0 | 0 |
| Shares issued for time vested restricted stock (net of forfeitures) (in shares)                | 129             | 1,918 | 1,368 |
| Shares issued for employee stock purchase plan (in shares)                                     | 88              | 203 | 375 |
| Outstanding, end of year (in shares)                                                           | 111,669         | 111,452 | 109,331 |

| X                                                                                                                                                                                                                                                                        |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Increase (Decrease) in Common Stock [Roll Forward]
+ References
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| - Definition
Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Number of shares issued under share-based payment arrangement.
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| - Definition
Number of shares issued during the period as a result of an employee stock purchase plan.
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|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Number of shares issued during the period related to Restricted Stock Awards, net of any shares forfeited.
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