|
Shareholders' Equity (Details) (USD $)
In Millions, except Share data, unless otherwise specified |
12 Months Ended | |||
|---|---|---|---|---|
|
Dec. 31, 2014
|
Dec. 31, 2013
|
Dec. 31, 2012
|
Sep. 24, 2013
|
|
| Equity, Class of Treasury Stock [Line Items] | ||||
| number of years | 2 | |||
| Dividends declared to shareholders | $ 8.3 | $ 8.3 | $ 7.7 | |
| 2012 Common Stock Repurchase Program [Member] | ||||
| Equity, Class of Treasury Stock [Line Items] | ||||
| Stock repurchase program, shares of common stock approved for repurchase | 250,000 | |||
| Stock repurchased during period, shares | 249,500 | |||
| Shares repurchased, average cost per share | $ 39.82 | |||
| The percentage of the stock repurchase program's allotment repurchased during the period | 99.80% | |||
| Share Repurchase Program, Shares Repurchased as Percentage of Shares Outstanding | 3.00% |