CONSOLIDATED STATEMENTS OF COMMON STOCKHOLDERS' EQUITY (UNAUDITED) - USD ($) $ in Millions	Total	Common Stock	Additional Paid In Capital	Retained Earnings	Accumulated Other Comprehensive Loss
Beginning balance (in shares) at Dec. 31, 2021		100
Beginning balance at Dec. 31, 2021	$ 3,603	$ 0	$ 3,091	$ 513	$ (1)
Increase (Decrease) in Stockholders' Equity
Net income	283			283
Dividends declared to parent	(261)			(261)
Contributions of capital by parent	210		210
Ending balance (in shares) at Sep. 30, 2022		100
Ending balance at Sep. 30, 2022	3,835	$ 0	3,301	535	(1)
Beginning balance (in shares) at Jun. 30, 2022		100
Beginning balance at Jun. 30, 2022	3,847	$ 0	3,301	547	(1)
Increase (Decrease) in Stockholders' Equity
Net income	138			138
Dividends declared to parent	(150)			(150)
Ending balance (in shares) at Sep. 30, 2022		100
Ending balance at Sep. 30, 2022	$ 3,835	$ 0	3,301	535	(1)
Beginning balance (in shares) at Dec. 31, 2022	100	100
Beginning balance at Dec. 31, 2022	$ 3,850	$ 0	3,311	540	(1)
Increase (Decrease) in Stockholders' Equity
Net income	302			302
Dividends declared to parent	(238)			(238)
Contributions of capital by parent	$ 47		47
Ending balance (in shares) at Sep. 30, 2023	100	100
Ending balance at Sep. 30, 2023	$ 3,961	$ 0	3,358	604	(1)
Beginning balance (in shares) at Jun. 30, 2023		100
Beginning balance at Jun. 30, 2023	3,825	$ 0	3,319	507	(1)
Increase (Decrease) in Stockholders' Equity
Net income	167			167
Dividends declared to parent	(70)			(70)
Contributions of capital by parent	$ 39		39
Ending balance (in shares) at Sep. 30, 2023	100	100
Ending balance at Sep. 30, 2023	$ 3,961	$ 0	$ 3,358	$ 604	$ (1)