| **Stock-based Compensation Plans - Restricted and Performance-based Award Activity (Details) (USD $)In Thousands, except Per Share data, unless otherwise specified** | 12 Months Ended |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------|-----------------|
||
| **Weighted Average Grant Date Fair Value**                                                                                                                            |            |   |   |
| Granted                                                                                                                                                               | $ 14.01         |   |   |
| Cash-settled Performance-based Stock Unit [Member]                                                                                                                    |            |   |   |
| **Shares**                                                                                                                                                            |            |   |   |
| Nonvested, at beginning of year                                                                                                                                       | 314             | 161 | 0 |
| Granted                                                                                                                                                               | 0               | 153 | 161 |
| Vested                                                                                                                                                                | 0               | 0 | 0 |
| Forfeited                                                                                                                                                             | (142)           | 0 | 0 |
| Nonvested, at end of year                                                                                                                                             | $ 68.03         | $ 84.75 | $ 0.00 |
| **Weighted Average Grant Date Fair Value**                                                                                                                            |            |   |   |
| Nonvested, at beginning of year                                                                                                                                       | 172             | 314 | 161 |
| Granted                                                                                                                                                               | $ 0.00          | $ 50.52 | $ 84.75 |
| Vested                                                                                                                                                                | $ 0.00          | $ 0.00 | $ 0.00 |
| Forfeited                                                                                                                                                             | $ 66.09         | $ 0.00 | $ 0.00 |
| Nonvested, at end of year                                                                                                                                             | $ 69.64         | $ 68.03 | $ 84.75 |
| Performance-based Stock Unit [Member]                                                                                                                                 |            |   |   |
| **Shares**                                                                                                                                                            |            |   |   |
| Nonvested, at beginning of year                                                                                                                                       | 0               |   |   |
| Granted                                                                                                                                                               | 762             |   |   |
| Vested                                                                                                                                                                | 0               |   |   |
| Forfeited                                                                                                                                                             | (110)           |   |   |
| Nonvested, at end of year                                                                                                                                             | $ 0.00          |   |   |
| **Weighted Average Grant Date Fair Value**                                                                                                                            |            |   |   |
| Nonvested, at beginning of year                                                                                                                                       | 652             |   |   |
| Granted                                                                                                                                                               | $ 28.19         |   |   |
| Vested                                                                                                                                                                | $ 0.00          |   |   |
| Forfeited                                                                                                                                                             | $ 27.24         |   |   |
| Nonvested, at end of year                                                                                                                                             | $ 28.35         |   |   |
| Restricted Stock [Member]                                                                                                                                             |            |   |   |
| **Shares**                                                                                                                                                            |            |   |   |
| Nonvested, at beginning of year                                                                                                                                       | 41              | 0 | 10 |
| Granted                                                                                                                                                               | 2               | 44 | 1 |
| Vested                                                                                                                                                                | (2)             | (3) | (10) |
| Forfeited                                                                                                                                                             | 0               |    | (1) |
| Nonvested, at end of year                                                                                                                                             | $ 24.13         | $ 0.00 | $ 35.81 |
| **Weighted Average Grant Date Fair Value**                                                                                                                            |            |   |   |
| Nonvested, at beginning of year                                                                                                                                       | 41              | 41 | 0 |
| Granted                                                                                                                                                               | $ 34.19         | $ 25.06 | $ 69.75 |
| Vested                                                                                                                                                                | $ 34.19         | $ 40.76 | $ 39.76 |
| Forfeited                                                                                                                                                             | $ 0.00          | $ 0.00 | $ 35.81 |
| Nonvested, at end of year                                                                                                                                             | $ 24.13         | $ 24.13 | $ 0.00 |
| Cash-Settled Restricted Stock Units [Member]                                                                                                                          |            |   |   |
| **Shares**                                                                                                                                                            |            |   |   |
| Nonvested, at beginning of year                                                                                                                                       | 463             | 393 | 275 |
| Granted                                                                                                                                                               | 3               | 285 | 225 |
| Vested                                                                                                                                                                | (215)           | (158) | (90) |
| Forfeited                                                                                                                                                             | (57)            | (57) | (17) |
| Nonvested, at end of year                                                                                                                                             | $ 43.20         | $ 48.80 | $ 35.81 |
| **Weighted Average Grant Date Fair Value**                                                                                                                            |            |   |   |
| Nonvested, at beginning of year                                                                                                                                       | 194             | 463 | 393 |
| Granted                                                                                                                                                               | $ 27.24         | $ 37.10 | $ 59.25 |
| Vested                                                                                                                                                                | $ 42.71         | $ 46.18 | $ 35.81 |
| Forfeited                                                                                                                                                             | $ 42.46         | $ 43.58 | $ 46.53 |
| Nonvested, at end of year                                                                                                                                             | $ 43.74         | $ 43.20 | $ 48.80 |
| Share-Settled Restricted Stock Units [Member]                                                                                                                         |            |   |   |
| **Shares**                                                                                                                                                            |            |   |   |
| Nonvested, at beginning of year                                                                                                                                       | 77              | 162 | 449 |
| Granted                                                                                                                                                               | 316             | 6 | 42 |
| Vested                                                                                                                                                                | (26)            | (90) | (323) |
| Forfeited                                                                                                                                                             | (68)            | (1) | (6) |
| Nonvested, at end of year                                                                                                                                             | $ 45.93         | $ 35.54 | $ 45.42 |
| **Weighted Average Grant Date Fair Value**                                                                                                                            |            |   |   |
| Nonvested, at beginning of year                                                                                                                                       | 299             | 77 | 162 |
| Granted                                                                                                                                                               | $ 28.13         | $ 42.19 | $ 53.72 |
| Vested                                                                                                                                                                | $ 35.84         | $ 27.22 | $ 51.33 |
| Forfeited                                                                                                                                                             | $ 39.13         | $ 33.97 | $ 48.35 |
| Nonvested, at end of year                                                                                                                                             | $ 29.54         | $ 45.93 | $ 35.54 |
| Performance-based Stock Options [Member]                                                                                                                              |            |   |   |
| **Share-based Compensation Arrangement by Share-based Payment Award [Line Items]**                                                                                    |            |   |   |
| Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other Than Options, Exercisable, Number                                         | 0               |   |   |
| **Shares**                                                                                                                                                            |            |   |   |
| Nonvested, at beginning of year                                                                                                                                       | 0               |   |   |
| Granted                                                                                                                                                               | 299             |   |   |
| Vested                                                                                                                                                                | 0               |   |   |
| Forfeited                                                                                                                                                             | 0               |   |   |
| Nonvested, at end of year                                                                                                                                             | $ 0.00          |   |   |
| **Weighted Average Grant Date Fair Value**                                                                                                                            |            |   |   |
| Nonvested, at beginning of year                                                                                                                                       | 299             |   |   |
| Granted                                                                                                                                                               | $ 34.47         |   |   |
| Vested                                                                                                                                                                | $ 0.00          |   |   |
| Forfeited                                                                                                                                                             | $ 0.00          |   |   |
| Nonvested, at end of year                                                                                                                                             | $ 34.47         |   |   |
| Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other Than Options, Exercisable, Weighted Average Exercise Price                | $ 0.00          |   |   |
| Market-based Stock Options [Member] [Member]                                                                                                                          |            |   |   |
| **Share-based Compensation Arrangement by Share-based Payment Award [Line Items]**                                                                                    |            |   |   |
| Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other Than Options, Exercisable, Number                                         | 0               |   |   |
| **Shares**                                                                                                                                                            |            |   |   |
| Nonvested, at beginning of year                                                                                                                                       | 0               |   |   |
| Granted                                                                                                                                                               | 917             |   |   |
| Vested                                                                                                                                                                | 0               |   |   |
| Forfeited                                                                                                                                                             | (158)           |   |   |
| Nonvested, at end of year                                                                                                                                             | $ 0.00          |   |   |
| **Weighted Average Grant Date Fair Value**                                                                                                                            |            |   |   |
| Nonvested, at beginning of year                                                                                                                                       | 759             |   |   |
| Granted                                                                                                                                                               | $ 27.24         |   |   |
| Vested                                                                                                                                                                | $ 0.00          |   |   |
| Forfeited                                                                                                                                                             | $ 27.24         |   |   |
| Nonvested, at end of year                                                                                                                                             | $ 27.24         |   |   |
| Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other Than Options, Exercisable, Weighted Average Exercise Price                | $ 0.00          |   |   |

| X                                                                                                                                                                                                                                                                                                                                                                                                                       |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other Than Options, Exercisable, Number
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No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other Than Options, Exercisable, Weighted Average Exercise Price
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.
+ References
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2)(iii)(3) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).
+ References
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).
+ References
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.
+ References
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units.
+ References
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.
+ References
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.
+ References
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