Share-Based Compensation (Details) (USD $) In Millions, except Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Share-Based Compensation
Stock based compensation expense	$ 1.1	$ 1.1	$ 3.6	$ 3.6
Stock options
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)			1.21%
Risk-free interest rate (as a percent)			0.92%
Average expected life			6 years
Expected volatility of common stock (as a percent)			44.60%
Forfeiture rate (as a percent)			0.00%
Weighted average fair value of option grants (in dollars per share)			$ 5.04
Restricted stock units | Directors
Assumptions used to determine value of the shares purchased under the stock purchase plan using Black-Scholes option pricing model
Granted (in shares)			27,492
2010 Incentive Plan | Stock options
Stock Compensation
Options granted (in shares)			173,558
2010 Incentive Plan | 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)			284,026
Vesting period			3 years
Granted (in dollars per share)			$ 13.24