XML 286 R168.htm IDEA: XBRL DOCUMENT v3.10.0.1
Stock-Based Compensation Plans - Schedule of Stock-based Compensation Expense (Details) - USD ($)
$ in Millions
3 Months Ended 12 Months Ended
Mar. 23, 2016
Dec. 31, 2018
Dec. 31, 2017
Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Allocated Share-based Compensation Expense   $ 208 $ 191 $ 175 [1]
Employee Service Share-based Compensation, Tax Benefit from Compensation Expense       (18)
Allocated Share-based Compensation Expense, Net of Tax   154 117 107 [1]
Performance Shares [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Allocated Share-based Compensation Expense   143 107 93 [1]
Employee Service Share-based Compensation, Tax Benefit from Compensation Expense   (16) (29) (18)
Restricted Stock Units (RSUs) [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Allocated Share-based Compensation Expense   57 77 75 [1]
Employee Service Share-based Compensation, Tax Benefit from Compensation Expense   (28) (35) (27)
Employee Stock Option [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Allocated Share-based Compensation Expense   0 0 0 [1]
Stock Compensation Plan [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Allocated Share-based Compensation Expense   8 7 7 [1]
Employee Service Share-based Compensation, Tax Benefit from Compensation Expense   $ (54) $ (74) $ (68) [1]
Predecessor [Member] | Pepco Holdings LLC [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Allocated Share-based Compensation Expense $ 3      
Employee Service Share-based Compensation, Tax Benefit from Compensation Expense (1)      
Allocated Share-based Compensation Expense, Net of Tax 2      
Predecessor [Member] | Pepco Holdings LLC [Member] | Performance Shares [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Allocated Share-based Compensation Expense 1      
Predecessor [Member] | Pepco Holdings LLC [Member] | Restricted Stock Units (RSUs) [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Allocated Share-based Compensation Expense 2      
Predecessor [Member] | Pepco Holdings LLC [Member] | Employee Stock Option [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Allocated Share-based Compensation Expense $ 0      
[1] (a)2016 amounts include expense related to stock-based compensation granted to eligible PHI employees since the merger date of March 23, 2016.