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Stock-Based Compensation - Additional Information (Details) - USD ($) $ / shares in Units, $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |
Allocated Share-based Compensation Expense | $ 14.7 | $ 12.9 | $ 10.8
Employee Service Share-based Compensation, Allocation of Recognized Period Costs, Capitalized Amount | 1.0 | 0.5 | 0.2
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized | $ 13.9 |  |
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition | 10 months 24 days |  |
Employee Service Share-based Compensation, Cash Flow Effect, Cash Used to Settle Awards | $ 3.7 | 2.9 | 4.8
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value | $ 9.3 | $ 7.6 | $ 10.5
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross | 0 | 0 | 0
Exercise of stock options, Shares | 69,852 |  |
Minimum [Member] | Risk Free Rate [Member] |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |
Requisite service period |  | 3 months | 3 months
Minimum [Member] | Volatility [Member] |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |
Requisite service period |  | 1 year | 3 years
Maximum [Member] | Risk Free Rate [Member] |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |
Requisite service period |  | 3 years | 3 years
Maximum [Member] | Volatility [Member] |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |
Requisite service period |  | 3 years | 1 year
Restricted Stock [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, Grants in Period, Weighted Average Grant Date Fair Value | $ 72.98 | $ 71.85 | $ 84.53
Requisite service period | 3 years | 3 years | 3 years
Restricted Stock [Member] | Maximum [Member] |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period | 5 years |  |
Employee Stock Option [Member] |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value | $ 1.2 |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term | 5 years 2 months 12 days |  |
Exercise of stock options, Shares | 69,852 | 17,823 | 21,006
Proceeds from Stock Options Exercised | $ 2.9 | $ 0.9 | $ 0.4
Employee Stock Option [Member] | Minimum [Member] |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period | 3 months 18 days |  |
Employee Stock Option [Member] | Maximum [Member] |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period | 2 years 3 months 18 days |  |
2013 Stock Incentive Plan [Member] |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized | 2,000,000 |  |

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