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, 2020		933,000
Beginning Balance at Dec. 31, 2020	$ 1,068	$ 93	$ 605	$ 370
Increase (Decrease) in Stockholder's Equity
Net income	46
Common dividends declared to parent	(34)			(34)
Contribution of capital by parent	33		33
Balance (in shares) at Jun. 30, 2021		933,000
Ending Balance at Jun. 30, 2021	1,113	$ 93	638	382
Balance (in shares) at Mar. 31, 2021		933,000
Beginning Balance at Mar. 31, 2021	1,110	$ 93	635	382
Increase (Decrease) in Stockholder's Equity
Net income	14			14
Common dividends declared to parent	(14)			(14)
Contribution of capital by parent	3		3
Balance (in shares) at Jun. 30, 2021		933,000
Ending Balance at Jun. 30, 2021	$ 1,113	$ 93	638	382
Balance (in shares) at Dec. 31, 2021	933,000	933,000
Beginning Balance at Dec. 31, 2021	$ 1,103	$ 93	642	368
Increase (Decrease) in Stockholder's Equity
Net income	62
Common dividends declared to parent	(41)			(41)
Contribution of capital by parent	$ 60		60
Balance (in shares) at Jun. 30, 2022	933,000	933,000
Ending Balance at Jun. 30, 2022	$ 1,184	$ 93	702	389
Balance (in shares) at Mar. 31, 2022		933,000
Beginning Balance at Mar. 31, 2022	1,158	$ 93	672	393
Increase (Decrease) in Stockholder's Equity
Net income	15			15
Common dividends declared to parent	(19)			(19)
Contribution of capital by parent	$ 30		30
Balance (in shares) at Jun. 30, 2022	933,000	933,000
Ending Balance at Jun. 30, 2022	$ 1,184	$ 93	$ 702	$ 389