Consolidated Statement of Shareholder's Interest - USD ($) $ in Millions	3 Months Ended						9 Months Ended
	Sep. 30, 2023	Jun. 30, 2023	Mar. 31, 2023	Sep. 30, 2022	Jun. 30, 2022	Mar. 31, 2022	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2021
Shareholder's Interest [Roll Forward]
Balance at beginning of period			$ 11,877				$ 11,877
Net income	$ 239	$ 286	240	$ 438	$ 804	$ 669	765	$ 1,911
Other Comprehensive Income (Loss), Net of Tax	(124)	18	88	(476)	(367)	152
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest, Beginning Balance	12,509	12,205	11,877	11,973	12,136	12,398	11,877	12,398
Distributions declared	0	0	0	(500)		(1,000)
Stockholders' Equity, Other					(600)	(83)
Balance at end of period	12,624						12,624
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest, Ending Balance	12,624	12,509	12,205	11,435	11,973	12,136	12,624	11,435
SHAREHOLDER’S INTEREST	0						0
Shareholder's Interest [Member]
Shareholder's Interest [Roll Forward]
Balance at beginning of period	5,166	5,166	5,166	5,166	5,166	5,227	5,166	5,227
Net income	0	0	0	0	0	0
Other Comprehensive Income (Loss), Net of Tax	0	0	0	0		0
Distributions declared	0	0	0	0	0	0
Stockholders' Equity, Other					0	(61)
Balance at end of period	5,166	5,166	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	(911)	(929)	(1,017)	(905)	(538)	(690)	(1,017)	(690)
Net income	0	0	0	0	0	0
Other Comprehensive Income (Loss), Net of Tax	(124)	18	88	(476)	(367)	152
Distributions declared	0	0	0	0		0
Stockholders' Equity, Other					0	0
Balance at end of period	(1,035)	(911)	(929)	(1,381)	(905)	(538)	(1,035)	(1,381)
Retained Earnings [Member]
Shareholder's Interest [Roll Forward]
Balance at beginning of period	8,254	7,968	7,728	7,712	7,508	7,839	7,728	7,839
Other Comprehensive Income (Loss), Net of Tax	0	0	0	0	0	0
Distributions declared	0	0	0	(500)	(600)	(1,000)
Stockholders' Equity, Other						0
Balance at end of period	8,493	8,254	7,968	7,650	7,712	7,508	8,493	7,650
Noncontrolling Interest
Shareholder's Interest [Roll Forward]
Net income	0	0	0	0	0	0
Other Comprehensive Income (Loss), Net of Tax	0	0	0	0	0	0
Distributions declared	0	0	0	0		0
Stockholders' Equity, Other					0	(22)
SHAREHOLDER’S INTEREST	0	0	0	0	0	0	0	0	$ 22
Parent [Member]
Shareholder's Interest [Roll Forward]
Balance at beginning of period	12,509	12,205
Net income	239	286	240	438	804	669
Other Comprehensive Income (Loss), Net of Tax	(124)	18	88	(476)	(367)	152
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest, Beginning Balance				11,973	12,136	12,376		12,376
Distributions declared	0	0	0	(500)		(1,000)
Stockholders' Equity, Other					(600)	(61)
Balance at end of period	$ 12,624	$ 12,509	$ 12,205				$ 12,624
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest, Ending Balance				$ 11,435	$ 11,973	$ 12,136		$ 11,435