Stock-Based Compensation (Asummptions used to estimate fair value for options) (Details) (USD $)	6 Months Ended
	Jun. 30, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term	6 years 6 months	[1]
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate	1.40%	[2]
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate	25.60%	[3]
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate	0.00%	[4]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value	$ 5.31

[1] Expected term calculated using the simplified method prescribed by the SEC due to the lack of sufficient historical exercise data on the grant date to provide a reasonable basis to estimate the expected term.

[2] Zero Coupon U.S. Treasury rate or equivalent based on expected term.

[3] Volatility calculated using the implied volatility of our exchange traded stock options.

[4] We have never paid cash dividends on our common stock, and we do not anticipate any cash dividend payments on our common stock in the near future.