Stock-Based Compensation (Details) - 2006 Plan - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Share-based compensation expense $ 3 $ 4 $ 5
Non-qualified stock options      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Contractual term (years) 5 years    
Stock appreciation rights (SAR)      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Contractual term (years) 7 years