CONSOLIDATED STATEMENT OF EQUITY (UNAUDITED) - USD ($) shares in Millions, $ in Millions	Total	Subsidiaries	Common Stock	Common Stock Subsidiaries	Additional Paid-In Capital	Additional Paid-In Capital Subsidiaries	Retained Earnings	Retained Earnings Subsidiaries	Treasury Stock	Capital Stock Expense	Accumulated Other Comprehensive Income/(Loss)	Accumulated Other Comprehensive Income/(Loss) Subsidiaries	Non- controlling Interest
Beginning balance (shares) at Dec. 31, 2020			342	235
Beginning balance at Dec. 31, 2020	$ 19,065		$ 36		$ 8,808		$ 11,178		$ (1,038)	$ (112)	$ (25)		$ 218
Beginning balance (shares) at Dec. 31, 2020									23
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	420						419						1
Common stock dividends	(265)	$ (247)					(265)	$ (247)
Issuance of common shares for stock plans	28				28
Other comprehensive income	4										4
Distributions to noncontrolling interest	(3)												(3)
Net proceeds from sale of equity interest	33												33
Ending balance (shares) at Mar. 31, 2021			342	235
Ending balance at Mar. 31, 2021	19,282		$ 36		8,836		11,332		$ (1,038)	(112)	(21)		249
Ending balance (shares) at Mar. 31, 2021									23
Increase (Decrease) in Stockholders' Equity [Roll Forward]
NET INCOME		465						465
Capital contribution by parent		125				$ 125
Beginning balance (shares) at Dec. 31, 2020			342	235
Beginning balance at Dec. 31, 2020	19,065		$ 36		8,808		11,178		$ (1,038)	(112)	(25)		218
Beginning balance (shares) at Dec. 31, 2020									23
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	538
Other comprehensive income	6
Ending balance (shares) at Jun. 30, 2021			353	235
Ending balance at Jun. 30, 2021	20,053		$ 37		9,655		11,231		$ (1,038)	(123)	(19)		310
Ending balance (shares) at Jun. 30, 2021									23
Increase (Decrease) in Stockholders' Equity [Roll Forward]
NET INCOME	584	593
Beginning balance (shares) at Mar. 31, 2021			342	235
Beginning balance at Mar. 31, 2021	19,282		$ 36		8,836		11,332		$ (1,038)	(112)	(21)		249
Beginning balance (shares) at Mar. 31, 2021									23
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	118						165						(47)
Common stock dividends	(266)	(247)					(266)	(247)
Issuance of common shares – public offering (shares)			11
Issuance of common shares - public offering	775		$ 1		785					(11)
Issuance of common shares for stock plans	34				34
Other comprehensive income	2										2
Distributions to noncontrolling interest	(4)												(4)
Net proceeds from sale of equity interest	112												112
Ending balance (shares) at Jun. 30, 2021			353	235
Ending balance at Jun. 30, 2021	20,053		$ 37		9,655		11,231		$ (1,038)	(123)	(19)		310
Ending balance (shares) at Jun. 30, 2021									23
Increase (Decrease) in Stockholders' Equity [Roll Forward]
NET INCOME	165	128						128
Capital contribution by parent		851				851
Beginning balance (shares) at Dec. 31, 2021			354	235
Beginning balance at Dec. 31, 2021	20,336		$ 37		9,710		11,445		$ (1,038)	(122)	5		299
Beginning balance (shares) at Dec. 31, 2021									23
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	554						602						(48)
Common stock dividends	(280)	(245)					(280)	(245)
Issuance of common shares - public offering	1									1
Issuance of common shares for stock plans	18				18
Other comprehensive income		1										$ 1
Distributions to noncontrolling interest	(6)												(6)
Ending balance (shares) at Mar. 31, 2022			354	235
Ending balance at Mar. 31, 2022	20,623		$ 37		9,728		11,767		$ (1,038)	(121)	5		245
Ending balance (shares) at Mar. 31, 2022									23
Increase (Decrease) in Stockholders' Equity [Roll Forward]
NET INCOME		475						475
Capital contribution by parent		75				75
Beginning balance (shares) at Dec. 31, 2021			354	235
Beginning balance at Dec. 31, 2021	20,336		$ 37		9,710		11,445		$ (1,038)	(122)	5		299
Beginning balance (shares) at Dec. 31, 2021									23
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	808
Other comprehensive income	5
Ending balance (shares) at Jun. 30, 2022			354	235
Ending balance at Jun. 30, 2022	20,621		$ 37		9,757		11,742		$ (1,038)	(121)	10		234
Ending balance (shares) at Jun. 30, 2022									23
Increase (Decrease) in Stockholders' Equity [Roll Forward]
NET INCOME	857	645
Beginning balance (shares) at Mar. 31, 2022			354	235
Beginning balance at Mar. 31, 2022	20,623		$ 37		9,728		11,767		$ (1,038)	(121)	5		245
Beginning balance (shares) at Mar. 31, 2022									23
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	254						255						(1)
Common stock dividends	(280)	(245)					(280)	(245)
Issuance of common shares for stock plans	29				29
Other comprehensive income	5										5
Distributions to noncontrolling interest	(10)												(10)
Ending balance (shares) at Jun. 30, 2022			354	235
Ending balance at Jun. 30, 2022	20,621		$ 37		$ 9,757		$ 11,742		$ (1,038)	$ (121)	$ 10		$ 234
Ending balance (shares) at Jun. 30, 2022									23
Increase (Decrease) in Stockholders' Equity [Roll Forward]
NET INCOME	$ 255	170						$ 170
Capital contribution by parent		$ 25				$ 25