Consolidated Statement of Shareholder's Interest - USD ($) $ in Millions	3 Months Ended				6 Months Ended
	Jun. 30, 2025	Mar. 31, 2025	Jun. 30, 2024	Mar. 31, 2024	Jun. 30, 2025	Jun. 30, 2024
Shareholder's Interest [Roll Forward]
Net income			$ 255		$ 967	$ 489
Balance at end of period	$ 14,544				14,544
Shareholder's Interest [Member]
Shareholder's Interest [Roll Forward]
Balance at beginning of period	5,166	$ 5,166	5,166	$ 5,166	5,166	5,166
Net income	0	0	0	0
Other Comprehensive Income (Loss), Net of Tax	0	0	0	0
Distributions declared	0	0	0
Balance at end of period	5,166	5,166	5,166	5,166	5,166	5,166
Accumulated Other Comprehensive Income/(Loss) (Note11) [Member]
Shareholder's Interest [Roll Forward]
Balance at beginning of period	(1,068)	(1,217)	(949)	(829)	(1,217)	(829)
Net income	0	0	0	0
Other Comprehensive Income (Loss), Net of Tax	371	149	(54)	(120)
Distributions declared	0	0	0
Balance at end of period	(697)	(1,068)	(1,003)	(949)	(697)	(1,003)
Retained Earnings [Member]
Shareholder's Interest [Roll Forward]
Balance at beginning of period	10,032	9,808	9,286	9,052	9,808	9,052
Net income	543	424	255	234
Other Comprehensive Income (Loss), Net of Tax	0	0	0	0
Distributions declared	(500)	(200)	(150)
Balance at end of period	10,075	10,032	9,391	9,286	10,075	9,391
Parent [Member]
Shareholder's Interest [Roll Forward]
Balance at beginning of period	14,130	13,757	13,503	13,389	13,757	13,389
Net income	543	424	255	234
Other Comprehensive Income (Loss), Net of Tax	371	149	(54)	(120)
Distributions declared	(500)	(200)	(150)
Balance at end of period	$ 14,544	$ 14,130	$ 13,554	$ 13,503	$ 14,544	$ 13,554