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Description of Business and Summary of Significant Accounting Policies (Employee Savings Plans) (Details) (USD $) In Millions, unless otherwise specified | 12 Months Ended
--- | ---
Dec. 31, 2013 | Dec. 31, 2012 | Dec. 31, 2011
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items] |  |  |
Matching contribution, 401(k) plan | $ 5.2 | $ 3.5 | $ 2.1
Balances due to participants | 51.7 | 40.6 |
Employer matching contribution [Member] |  |  |
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items] |  |  |
Matching contributions to employee participants | $ 0.5 | $ 0.5 | $ 0.6
Deferred compensation arrangement with individual matching contribution annual vesting years two and three | 33.00% |  |
Deferred compensation arrangement with individual matching contribution annual vesting portion, year one | 33.00% |  |
Employer discretionary contribution [Member] |  |  |
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items] |  |  |
Employer contributions vesting periods (in years) | 3 years |  |
Employees Hired Subsequent to January 1, 2011 [Member] |  |  |
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items] |  |  |
401(k) plan matching contribution requisite service period | 3 years |  |

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- Definition Portion of employer's matching contributions to a deferred compensation plan that is vested and credited to participants on the first business day of the subsequent calendar year. + References No definition available. + Details
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- Definition Portion of employer's matching contributions to a deferred compensation plan that is vested and credited to participants on the second and third anniversaries of the first business day of the subsequent calendar year after the date of the contribution. + References No definition available. + Details
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- Definition The minimum period that the individual is required to perform services in order to be fully vested under the deferred compensation arrangement. + References No definition available. + Details
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- Definition Amount of matching contributions made by an employer to a defined contribution plan. + References No definition available. + Details
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- Definition The minimum period that the individual is required to perform services in order to be fully vested for matching contributions under the defined contribution plan. + References No definition available. + Details
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- Definition The amount of payment into the fund established for purposes of making future disbursements to the individual in accordance with the terms and understanding of the deferred compensation arrangement. + References No definition available. + Details
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- Details
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- Definition Aggregate carrying value as of the balance sheet date of the liabilities for all deferred compensation arrangements. Represents currently earned compensation under compensation arrangements that is not actually paid until a later date. + References No definition available. + Details
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