Employee Stock and Benefit Plans (Assumptions in Option Pricing Model) (Details)
12 Months Ended
Dec. 31, 2014
Dec. 31, 2013
Dec. 31, 2012
Share-based Compensation, Allocation and Classification in Financial Statements [Abstract]      
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate, Minimum 0.00% 0.00% 0.00%
Expected dividend yield 0.00% 0.00% 0.00%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate, Maximum 0.00% 0.00% 0.00%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate, Minimum 0.00% 0.00% 0.00%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate, Maximum 0.00% 0.00% 0.00%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term in Years, Minimum 4.78 4.78 4.65
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term in Years, Maximum 4.81 4.81 4.78