Income Taxes (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Income Taxes
Effective income tax rates (as a percent)	39.50%	39.20%	39.50%	39.00%
Uncertain tax positions	$ 0		$ 0