| **Stock Based Compensation - Narrative (Details) - USD ($) $ / shares in Units, $ in Millions** |           | 12 Months Ended |
|-------------------------------------------------------------------------------------------------|-----------|-----------------|
||
| **Share-based Compensation Arrangement by Share-based Payment Award [Line Items]**              |      |            |   |   |
| Total stock based compensation cost recognized                                                  |      | $ 11.9          | $ 12.7 | $ 13.3 |
| Stock option compensation expense recognized                                                    |      | $ 5.1           | $ 6.2 | $ 6.4 |
| Weighted-average fair value per option at the date of grant (in dollars per share)              |      | $ 14.03         | $ 8.17 | $ 10.83 |
| Employee Stock Option                                                                           |      |            |   |   |
| **Share-based Compensation Arrangement by Share-based Payment Award [Line Items]**              |      |            |   |   |
| Award vesting period                                                                            |      | 3 years         | 3 years | 3 years |
| Award expiration period                                                                         |      | 10 years        | 10 years | 10 years |
| Restricted Stock And Share Units                                                                |      |            |   |   |
| **Share-based Compensation Arrangement by Share-based Payment Award [Line Items]**              |      |            |   |   |
| Award vesting period                                                                            |      | 3 years         |   |   |
| Number of share units granted (in shares)                                                       |      | 104,312         | 174,420 | 140,102 |
| Value of share units granted                                                                    |      | $ 6.4           | $ 7.4 | $ 6.9 |
| Share based compensation expense attributable to share units                                    |      | $ 6.8           | $ 6.5 | $ 6.9 |
| Incentive Plan                                                                                  |      |            |   |   |
| **Share-based Compensation Arrangement by Share-based Payment Award [Line Items]**              |      |            |   |   |
| Number of shares available for granting of options, restricted stock or share units (in shares) |      | 2,962,559       |   |   |
| Additional shares authorized (in shares)                                                        | 2,400,000 |            |   |   |

| X                                                                                                                                                                                                                                                                                                                                                                                                                                            |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Fair Value
+ References
No definition available.
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|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.
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| - Definition
Amount of noncash expense for award of restricted stock or unit under share-based payment arrangement.
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|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.
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|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - 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).
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| - 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.
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No definition available.
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|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Number of additional shares authorized for issuance under share-based payment arrangement.
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|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.
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| - Definition
Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.
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| - Definition
Amount of noncash expense for option under share-based payment arrangement.
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