Consolidated Statements of Operations (Unaudited) - USD ($)
shares in Millions, $ in Millions
3 Months Ended
Mar. 31, 2021
Mar. 31, 2020
Income Statement [Abstract]    
Operating revenues $ 888 $ 844
Operating expenses:    
Operation and maintenance 419 383
Depreciation and amortization 157 145
General taxes 83 77
Total operating expenses, net 659 605
Operating income 229 239
Other income (expense):    
Interest, net (98) (96)
Non-operating benefit costs, net 20 13
Other, net 4 3
Total other income (expense) (74) (80)
Income before income taxes 155 159
Provision for income taxes 22 35
Net income attributable to common shareholders $ 133 $ 124
Basic earnings per share:    
Net income attributable to common shareholders (dollars per share) $ 0.73 $ 0.69
Diluted earnings per share:    
Net income attributable to common shareholders (dollars per share) [1] $ 0.73 $ 0.68
Weighted-average common shares outstanding:    
Basic (shares) 181 181
Diluted (shares) 182 181
[1] Amounts may not calculate due to rounding.