Deferred Compensation Plan (Details) - USD ($) $ in Millions |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2016 |
Dec. 31, 2015 |
Dec. 31, 2014 |
|
| Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items] | |||
| Deferred compensation plan liability | $ 12.0 | $ 11.6 | |
| Cash surrender value of the policies | 15.6 | 15.4 | |
| Benefits paid | $ 1.4 | $ 1.7 | $ 1.9 |
| Employee | |||
| Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items] | |||
| Percentage of receipt of base compensation (up to) | 75.00% | ||
| Non Employee Director | |||
| Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items] | |||
| Percentage of receipt of base compensation (up to) | 100.00% |