CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Statement of Comprehensive Income [Abstract]
Net Income	$ 351	$ 459	$ 1,333	$ 1,297
Other Comprehensive Income
Pension and other postretirement benefit plans obligations (net of taxes of $0, $0, $0, and $0, respectively)	0	0	0	0
Net unrealized gains (losses) on available-for-sale securities (net of taxes of $0, $5, $2, and $7, respectively)	(2)	(12)	3	(17)
Total other comprehensive income (loss)	(2)	(12)	3	(17)
Comprehensive Income	349	447	1,336	1,280
Preferred stock dividend requirement of subsidiary	3	3	10	10
Comprehensive Income Available for Common Shareholders	$ 346	$ 444	$ 1,326	$ 1,270