Employee Benefit Plans - Weighted Average Assumptions on Option Pricing (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Performance Stock Options [Member]
Employee benefit plans [Line Items]
Dividend yield (as a percent)		2.07%	2.06%
Expected volatility (as a percent)		53.50%	58.89%
Risk free interest rate (as a percent)		1.36%	1.45%
Expected life (in years)		6 years 3 months 18 days	6 years 3 months 18 days
Forfeiture rate (as a percent)		4.50%	4.50%
Weighted average grant date fair value (in dollars per share)	$ 0.00	$ 8.17	$ 7.84
Stock Options [Member]
Employee benefit plans [Line Items]
Dividend yield (as a percent)	2.03%	2.07%	2.06%
Expected volatility (as a percent)	53.24%	53.41%	58.89%
Risk free interest rate (as a percent)	2.21%	1.35%	1.45%
Expected life (in years)	6 years 7 months 6 days	6 years 7 months 6 days	6 years 7 months 6 days
Forfeiture rate (as a percent)	3.50%	4.50%	4.50%
Weighted average grant date fair value (in dollars per share)	$ 10.35	$ 8.94	$ 8.62