Condensed Statements of Consolidated Changes in Equity (Unaudited) - USD ($) $ in Millions	Total	Preferred Stock	Preferred Stock Series B and Series C Preferred Stock	Common Stock	Additional Paid-in Capital	Retained Earnings	AOCI Attributable to Parent
Balance, beginning of period (in shares) at Dec. 31, 2020		3,000,000
Balance, beginning of period at Dec. 31, 2020		$ 2,363		$ 6	$ 6,914	$ (845)	$ (90)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Conversion of Series B Preferred Stock and Series C Preferred Stock (in shares)			0
Conversion of Series B Preferred Stock and Series C Preferred Stock			$ (624)
Balance, end of period (in shares) at Jun. 30, 2021		3,000,000
Balance, beginning of period (in shares) at Dec. 31, 2020				551,000,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuances of Common Stock (in shares)				41,000,000
Issuances of Common Stock				$ 0	624
Issuances related to benefit and investment plans (in shares)				1,000,000
Issuances related to benefit and investment plans				$ 0	15
Net income	$ 614					614
Common Stock dividends declared (see Note 18)						(95)
Preferred Stock dividends declared (see Note 18)						(17)
Other comprehensive income (loss)							5
Balance, end of period (in shares) at Jun. 30, 2021				593,000,000
Balance, end of period at Jun. 30, 2021	8,870	$ 1,739		$ 6	7,553	(343)	(85)
Balance, beginning of period (in shares) at Mar. 31, 2021		3,000,000
Balance, beginning of period at Mar. 31, 2021		$ 2,363		$ 6	6,916	(482)	(87)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Conversion of Series B Preferred Stock and Series C Preferred Stock (in shares)			0
Conversion of Series B Preferred Stock and Series C Preferred Stock			$ (624)
Balance, end of period (in shares) at Jun. 30, 2021		3,000,000
Balance, beginning of period (in shares) at Mar. 31, 2021				552,000,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuances of Common Stock (in shares)				41,000,000
Issuances of Common Stock				$ 0	624
Issuances related to benefit and investment plans (in shares)				0
Issuances related to benefit and investment plans				$ 0	13
Net income	251					251
Common Stock dividends declared (see Note 18)						(95)
Preferred Stock dividends declared (see Note 18)						(17)
Other comprehensive income (loss)							2
Balance, end of period (in shares) at Jun. 30, 2021				593,000,000
Balance, end of period at Jun. 30, 2021	$ 8,870	$ 1,739		$ 6	7,553	(343)	(85)
Balance, beginning of period (in shares) at Dec. 31, 2021	800,000	1,000,000
Balance, beginning of period at Dec. 31, 2021	$ 9,415	$ 790		$ 6	8,529	154	(64)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Conversion of Series B Preferred Stock and Series C Preferred Stock (in shares)			0
Conversion of Series B Preferred Stock and Series C Preferred Stock			$ 0
Balance, end of period (in shares) at Jun. 30, 2022	800,000	1,000,000
Balance, beginning of period (in shares) at Dec. 31, 2021	628,923,534			629,000,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuances of Common Stock (in shares)				0
Issuances of Common Stock				$ 0	0
Issuances related to benefit and investment plans (in shares)				0
Issuances related to benefit and investment plans				$ 0	15
Net income	$ 721					721
Common Stock dividends declared (see Note 18)						(107)
Preferred Stock dividends declared (see Note 18)						0
Other comprehensive income (loss)							(21)
Balance, end of period (in shares) at Jun. 30, 2022	629,490,422			629,000,000
Balance, end of period at Jun. 30, 2022	$ 10,023	$ 790		$ 6	8,544	768	(85)
Balance, beginning of period (in shares) at Mar. 31, 2022		1,000,000
Balance, beginning of period at Mar. 31, 2022		$ 790		$ 6	8,532	685	(62)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Conversion of Series B Preferred Stock and Series C Preferred Stock (in shares)			0
Conversion of Series B Preferred Stock and Series C Preferred Stock			$ 0
Balance, end of period (in shares) at Jun. 30, 2022	800,000	1,000,000
Balance, beginning of period (in shares) at Mar. 31, 2022				629,000,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuances of Common Stock (in shares)				0
Issuances of Common Stock				$ 0	0
Issuances related to benefit and investment plans (in shares)				0
Issuances related to benefit and investment plans				$ 0	12
Net income	$ 190					190
Common Stock dividends declared (see Note 18)						(107)
Preferred Stock dividends declared (see Note 18)						0
Other comprehensive income (loss)							(23)
Balance, end of period (in shares) at Jun. 30, 2022	629,490,422			629,000,000
Balance, end of period at Jun. 30, 2022	$ 10,023	$ 790		$ 6	$ 8,544	$ 768	$ (85)