| **Incentive Plans and Stock-Based Compensation - Stock Options Exercise Prices (Details) - USD ($) $ / shares in Units, $ in Thousands** | 3 Months Ended            |           |
|------------------------------------------------------------------------------------------------------------------------------------------|---------------------------|-----------|
||
| $25.31 - $28.13 [Member]                                                                                                                 |                      |      |
| **Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]**                              |                      |      |
| Exercise price range, minimum (in dollars per share)                                                                                     | $ 25.31                   |      |
| Exercise price range, maximum (in dollars per share)                                                                                     | 28.13                     |      |
| $31.96 - $36.48 [Member]                                                                                                                 |                      |      |
| **Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]**                              |                      |      |
| Exercise price range, minimum (in dollars per share)                                                                                     | 31.96                     |      |
| Exercise price range, maximum (in dollars per share)                                                                                     | 36.48                     |      |
| $42.86 - $46.80 [Member]                                                                                                                 |                      |      |
| **Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]**                              |                      |      |
| Exercise price range, minimum (in dollars per share)                                                                                     | 42.86                     |      |
| Exercise price range, maximum (in dollars per share)                                                                                     | 46.80                     |      |
| $49.35 - $63.22 [Member]                                                                                                                 |                      |      |
| **Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]**                              |                      |      |
| Exercise price range, minimum (in dollars per share)                                                                                     | 49.35                     |      |
| Exercise price range, maximum (in dollars per share)                                                                                     | $ 63.22                   |      |
| Employee and Non-Employee Stock Options [Member]                                                                                         |                      |      |
| **Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]**                              |                      |      |
| Options outstanding (in shares)                                                                                                          | 2,666,050                 | 2,422,538 |
| Options outstanding weighted average exercise price (in dollars per share)                                                               | $ 48.32                   | $ 48.46   |
| Options outstanding - intrinsic value                                                                                                    | $ 10,497                  |      |
| Options outstanding - weighted average remaining life in years                                                                           | 6 years 5 months 12 days  |      |
| Options exercisable - number (in shares)                                                                                                 | 1,935,719                 |      |
| Options exercisable - weighted average exercise price (in dollars per share)                                                             | $ 46.09                   |      |
| Options exercisable - intrinsic value                                                                                                    | $ 9,773                   |      |
| Options exercisable - weighted average remaining life in years                                                                           | 5 years 6 months 15 days  |      |
| Employee and Non-Employee Stock Options [Member] | $25.31 - $28.13 [Member]                                                              |                      |      |
| **Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]**                              |                      |      |
| Options outstanding (in shares)                                                                                                          | 32,000                    |      |
| Options outstanding weighted average exercise price (in dollars per share)                                                               | $ 25.49                   |      |
| Options outstanding - intrinsic value                                                                                                    | $ 726                     |      |
| Options outstanding - weighted average remaining life in years                                                                           | 2 years 11 months 1 day   |      |
| Options exercisable - number (in shares)                                                                                                 | 32,000                    |      |
| Options exercisable - weighted average exercise price (in dollars per share)                                                             | $ 25.49                   |      |
| Options exercisable - intrinsic value                                                                                                    | $ 726                     |      |
| Options exercisable - weighted average remaining life in years                                                                           | 2 years 11 months 1 day   |      |
| Employee and Non-Employee Stock Options [Member] | $31.96 - $36.48 [Member]                                                              |                      |      |
| **Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]**                              |                      |      |
| Options outstanding (in shares)                                                                                                          | 424,821                   |      |
| Options outstanding weighted average exercise price (in dollars per share)                                                               | $ 33.61                   |      |
| Options outstanding - intrinsic value                                                                                                    | $ 6,190                   |      |
| Options outstanding - weighted average remaining life in years                                                                           | 2 years 8 months 16 days  |      |
| Options exercisable - number (in shares)                                                                                                 | 424,821                   |      |
| Options exercisable - weighted average exercise price (in dollars per share)                                                             | $ 33.61                   |      |
| Options exercisable - intrinsic value                                                                                                    | $ 6,190                   |      |
| Options exercisable - weighted average remaining life in years                                                                           | 2 years 8 months 16 days  |      |
| Employee and Non-Employee Stock Options [Member] | $42.86 - $46.80 [Member]                                                              |                      |      |
| **Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]**                              |                      |      |
| Options outstanding (in shares)                                                                                                          | 1,037,476                 |      |
| Options outstanding weighted average exercise price (in dollars per share)                                                               | $ 44.73                   |      |
| Options outstanding - intrinsic value                                                                                                    | $ 3,581                   |      |
| Options outstanding - weighted average remaining life in years                                                                           | 7 years 4 days            |      |
| Options exercisable - number (in shares)                                                                                                 | 669,204                   |      |
| Options exercisable - weighted average exercise price (in dollars per share)                                                             | $ 43.91                   |      |
| Options exercisable - intrinsic value                                                                                                    | $ 2,857                   |      |
| Options exercisable - weighted average remaining life in years                                                                           | 5 years 8 months 23 days  |      |
| Employee and Non-Employee Stock Options [Member] | $49.35 - $63.22 [Member]                                                              |                      |      |
| **Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]**                              |                      |      |
| Options outstanding (in shares)                                                                                                          | 1,171,753                 |      |
| Options outstanding weighted average exercise price (in dollars per share)                                                               | $ 57.46                   |      |
| Options outstanding - intrinsic value                                                                                                    | $ 0                       |      |
| Options outstanding - weighted average remaining life in years                                                                           | 7 years 4 months 24 days  |      |
| Options exercisable - number (in shares)                                                                                                 | 809,694                   |      |
| Options exercisable - weighted average exercise price (in dollars per share)                                                             | $ 55.25                   |      |
| Options exercisable - intrinsic value                                                                                                    | $ 0                       |      |
| Options exercisable - weighted average remaining life in years                                                                           | 6 years 11 months 19 days |      |

| 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
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)(1)(iii) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock 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
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1)(i)-(ii) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.
+ 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 floor of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.
+ References
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The ceiling of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.
+ 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
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.
+ References
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.
+ References
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| X                                                                                                                                                          |
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