Share-Based Compensation (Details) (USD $) In Millions, except Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Share-Based Compensation
Stock based compensation expense	$ 1.5	$ 1.7
Employee Stock Option
Assumptions used to determine value of the shares purchased under the stock purchase plan using Black-Scholes option pricing model
Expected annual dividend rate (as a percent)	1.18%
Risk-free interest rate (as a percent)	1.62%
Average expected life	6 years
Expected volatility of common stock (as a percent)	0.401%
Forfeiture rate (as a percent)	0.00%
Weighted average fair value of option grants	$ 4.75
Restricted Stock Units (RSUs) | Director
Assumptions used to determine value of the shares purchased under the stock purchase plan using Black-Scholes option pricing model
Granted (in shares)	31,088
Performance Restricted Stock Units
Assumptions used to determine value of the shares purchased under the stock purchase plan using Black-Scholes option pricing model
Vesting period	3 years
Long Term Incentive Plan 2010 | Employee Stock Option
Stock Compensation
Options granted (in shares)	237,240
Long Term Incentive Plan 2010 | Restricted Stock Units (RSUs)
Assumptions used to determine value of the shares purchased under the stock purchase plan using Black-Scholes option pricing model
Granted (in shares)	386,401
Vesting period	3 years
Granted (in dollars per share)	$ 13.51
Long Term Incentive Plan 2010 | Performance Restricted Stock Units
Assumptions used to determine value of the shares purchased under the stock purchase plan using Black-Scholes option pricing model
Granted (in shares)	202,505