Schedule I - Condensed Financial Information Of Parent (Balance Sheet) (Details) - USD ($) $ / shares in Units, $ in Millions	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Assets:
Cash and cash equivalents	$ 10	$ 8
Miscellaneous accounts and notes receivable	54	85
Other current assets	155	155
Total current assets	2,668	1,968
Other assets	768	891
Total assets	37,904	35,735
Liabilities and Shareholders' Equity:
Short-term debt	1,070	545
Other current liabilities	797	681
Total current liabilities	3,366	2,826
Long-term debt	13,685	12,562
Other deferred credits and liabilities	340	414
Commitments and Contingencies (Note 5)
Common stock, $.01 par value, 400.0 shares authorized – shares outstanding of 262.0 and 257.7, respectively	3	3
Other paid-in capital, principally premium on common stock	6,860	6,502
Retained earnings	3,646	3,182
Accumulated other comprehensive income (loss)	(1)	13
Total shareholders’ equity	10,637	9,829	$ 9,080
TOTAL LIABILITIES AND EQUITY	$ 37,904	$ 35,735
Common Stock, Par or Stated Value Per Share (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized	400,000,000.0	400,000,000.0
Common Stock, Shares, Outstanding	262,000,000.0	257,700,000	253,300,000	246,200,000
Parent Company
Assets:
Cash and cash equivalents	$ 0	$ 0
Advances to money pool	68	108
Accounts receivable – affiliates	59	30
Miscellaneous accounts and notes receivable	11	11
Other current assets	0	4
Total current assets	138	153
Investments in subsidiaries	13,394	12,281
Note receivable – ATXI	0	35
Accumulated deferred income taxes, net	46	65
Other assets	137	184
Total assets	13,715	12,718
Liabilities and Shareholders' Equity:
Short-term debt	477	277
Taxes accrued	5	7
Accounts payable – affiliates	52	53
Other current liabilities	41	38
Total current liabilities	575	375
Long-term debt	2,536	2,533
Pension and other postretirement benefits	19	24
Other deferred credits and liabilities	77	86
Total liabilities	3,207	3,018
Commitments and Contingencies (Note 5)
Common stock, $.01 par value, 400.0 shares authorized – shares outstanding of 262.0 and 257.7, respectively	3	3
Other paid-in capital, principally premium on common stock	6,860	6,502
Retained earnings	3,646	3,182
Accumulated other comprehensive income (loss)	(1)	13
Total shareholders’ equity	10,508	9,700
TOTAL LIABILITIES AND EQUITY	$ 13,715	$ 12,718
Common Stock, Par or Stated Value Per Share (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized	400,000,000.0	400,000,000.0
Common Stock, Shares, Outstanding	262,000,000.0	257,700,000