Consolidated Statement of Shareholder's Interest - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Dec. 31, 2020	Mar. 31, 2020	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Total shareholder’s interest	$ 15,567		$ 12,398	$ 15,567	$ 16,389	$ 16,625
Shareholder's Interest [Roll Forward]
Balance at beginning of period			15,567
Net income	827	$ (6)	4,521	2,338	2,620
Other comprehensive income/(loss), net of tax			(212)	372	44
Balance at end of period	15,567		12,376	15,567
Stockholders' interest attributable to noncontrolling interest	0		22	0
Shareholder's Interest [Member]
Shareholder's Interest [Roll Forward]
Balance at beginning of period		5,227	5,227	5,227	5,227
Net income			0	0	0
Other comprehensive income/(loss), net of tax			0	0	0
Distributions declared			0	0	0
Stockholders' Equity, Other			0
Balance at end of period	5,227		5,227	5,227	5,227
Accumulated Other Comprehensive Income/(Loss) (Note11) [Member]
Shareholder's Interest [Roll Forward]
Balance at beginning of period		(850)	(478)	(850)	(894)
Net income			0	0	0
Other comprehensive income/(loss), net of tax			(212)	372	44
Distributions declared			0	0	0
Stockholders' Equity, Other			0
Balance at end of period	(478)		(690)	(478)	(850)
Retained Earnings [Member]
Shareholder's Interest [Roll Forward]
Balance at beginning of period		$ 12,012	10,818	12,012	12,292
Net income			4,521	2,338	2,620
Other comprehensive income/(loss), net of tax			0	0	0
Distributions declared			(7,500)	(3,290)	(2,900)
Stockholders' Equity, Other			0
Balance at end of period	10,818		7,839	10,818	12,012
Parent [Member]
Total shareholder’s interest					16,389	16,625
Shareholder's Interest [Roll Forward]
Balance at beginning of period			15,567
Distributions declared			(7,500)	(3,290)	(2,900)
Stockholders' Equity, Other			0
Balance at end of period	15,567		12,376	15,567
Noncontrolling Interest [Member]
Total shareholder’s interest					0
Shareholder's Interest [Roll Forward]
Net income			0	0	0
Other comprehensive income/(loss), net of tax			0	0	0
Distributions declared			0	0	0
Stockholders' Equity, Other			22
Stockholders' interest attributable to noncontrolling interest	0		$ 22	0	$ 0	$ 0
Accounting Standards Update 2016-13 [Member]
Total shareholder’s interest	(242)			(242)
Accounting Standards Update 2016-13 [Member] | Shareholder's Interest [Member]
Total shareholder’s interest	0			0
Accounting Standards Update 2016-13 [Member] | Accumulated Other Comprehensive Income/(Loss) (Note11) [Member]
Total shareholder’s interest	0			0
Accounting Standards Update 2016-13 [Member] | Retained Earnings [Member]
Total shareholder’s interest	(242)			(242)
Accounting Standards Update 2016-13 [Member] | Noncontrolling Interest [Member]
Total shareholder’s interest	$ 0			$ 0