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, 2023		100
Beginning balance at Dec. 31, 2023	$ 3,986	$ 0	$ 3,370	$ 617	$ (1)
Increase (Decrease) in Stockholders' Equity
Net income	322			322
Dividends declared to parent	(318)			(318)
Contributions of capital by parent	267		267
Ending balance (in shares) at Sep. 30, 2024		100
Ending balance at Sep. 30, 2024	4,257	$ 0	3,637	621	(1)
Beginning balance (in shares) at Jun. 30, 2024		100
Beginning balance at Jun. 30, 2024	4,260	$ 0	3,633	628	(1)
Increase (Decrease) in Stockholders' Equity
Net income	176			176
Dividends declared to parent	(183)			(183)
Contributions of capital by parent	4		4
Ending balance (in shares) at Sep. 30, 2024		100
Ending balance at Sep. 30, 2024	$ 4,257	$ 0	3,637	621	(1)
Beginning balance (in shares) at Dec. 31, 2024	100	100
Beginning balance at Dec. 31, 2024	$ 4,238	$ 0	3,647	592	(1)
Increase (Decrease) in Stockholders' Equity
Net income	320			320
Dividends declared to parent	(268)			(268)
Contributions of capital by parent	$ 555		555
Ending balance (in shares) at Sep. 30, 2025	100	100
Ending balance at Sep. 30, 2025	$ 4,845	$ 0	4,202	644	(1)
Beginning balance (in shares) at Jun. 30, 2025		100
Beginning balance at Jun. 30, 2025	4,846	$ 0	4,200	647	(1)
Increase (Decrease) in Stockholders' Equity
Net income	160			160
Dividends declared to parent	(163)			(163)
Contributions of capital by parent	$ 2		2
Ending balance (in shares) at Sep. 30, 2025	100	100
Ending balance at Sep. 30, 2025	$ 4,845	$ 0	$ 4,202	$ 644	$ (1)