Share-Based Compensation (Details) (USD $) In Millions, except Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Share-Based Compensation
Stock based compensation expense	$ 1.3	$ 1.3
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	44.60%
Forfeiture rate (as a percent)	0.00%
Weighted average fair value of option grants (in dollars per share)	$ 5.04
Restricted Stock | 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
Assumptions used to determine value of the shares purchased under the stock purchase plan using Black-Scholes option pricing model
Granted (in shares)	173,558
2010 Incentive Plan | Restricted Stock
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