CONSOLIDATED STATEMENTS OF COMMON STOCKHOLDER'S EQUITY - USD ($) $ in Millions	Total	Common stock	Additional Paid In Capital	Retained Earnings
Balance (in shares) at Dec. 31, 2021		933,000
Beginning Balance at Dec. 31, 2021	$ 1,103	$ 93	$ 642	$ 368
Increase (Decrease) in Stockholder's Equity
Net income	102
Common dividends declared to parent	(64)			(64)
Contribution of capital by parent	110		110
Balance (in shares) at Sep. 30, 2022		933,000
Ending Balance at Sep. 30, 2022	1,251	$ 93	752	406
Balance (in shares) at Jun. 30, 2022		933,000
Beginning Balance at Jun. 30, 2022	1,184	$ 93	702	389
Increase (Decrease) in Stockholder's Equity
Net income	40			40
Common dividends declared to parent	(23)			(23)
Contribution of capital by parent	50		50
Balance (in shares) at Sep. 30, 2022		933,000
Ending Balance at Sep. 30, 2022	$ 1,251	$ 93	752	406
Balance (in shares) at Dec. 31, 2022	933,000	933,000
Beginning Balance at Dec. 31, 2022	$ 1,259	$ 93	761	405
Increase (Decrease) in Stockholder's Equity
Net income	102
Common dividends declared to parent	(73)			(73)
Contribution of capital by parent	$ 59		59
Balance (in shares) at Sep. 30, 2023	933,000	933,000
Ending Balance at Sep. 30, 2023	$ 1,347	$ 93	820	434
Balance (in shares) at Jun. 30, 2023		933,000
Beginning Balance at Jun. 30, 2023	1,326	$ 93	806	427
Increase (Decrease) in Stockholder's Equity
Net income	31			31
Common dividends declared to parent	(24)			(24)
Contribution of capital by parent	$ 14		14
Balance (in shares) at Sep. 30, 2023	933,000	933,000
Ending Balance at Sep. 30, 2023	$ 1,347	$ 93	$ 820	$ 434