CONSOLIDATED STATEMENT OF CHANGES IN EQUITY (UNAUDITED) - USD ($) $ in Millions	Total	Preferred stock	Common stock	Additional paid-in capital	Retained earnings	Accumulated other comprehensive income (loss)
Balance at beginning of period at Dec. 31, 2020		$ 1,265
Balance at beginning of period, common equity at Dec. 31, 2020			$ 0	$ 15,746	$ 601	$ 679
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Return of capital to parent				0
Employee benefit plans				(3)
Net income	$ 669				669
Cash dividends declared on preferred stock					(38)
Other comprehensive loss, net of tax	(682)					(682)
Balance at end of period, common equity at Sep. 30, 2021	16,972		0	15,743	1,232	(3)
Balance at end of period at Sep. 30, 2021	18,237	1,265
Balance at beginning of period at Jun. 30, 2021		1,265
Balance at beginning of period, common equity at Jun. 30, 2021			0	15,743	1,095	81
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Return of capital to parent				0
Employee benefit plans				0
Net income	137				137
Other comprehensive loss, net of tax	(84)					(84)
Balance at end of period, common equity at Sep. 30, 2021	16,972		0	15,743	1,232	(3)
Balance at end of period at Sep. 30, 2021	18,237	1,265
Balance at beginning of period at Dec. 31, 2021	17,040	1,265
Balance at beginning of period, common equity at Dec. 31, 2021	15,775		0	14,742	1,212	(179)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Return of capital to parent				(1,000)
Employee benefit plans				(3)
Net income	452				452
Cash dividends declared on preferred stock					(38)
Other comprehensive loss, net of tax	(2,418)					(2,418)
Balance at end of period, common equity at Sep. 30, 2022	12,768		0	13,739	1,626	(2,597)
Balance at end of period at Sep. 30, 2022	14,033	1,265
Balance at beginning of period at Jun. 30, 2022		1,265
Balance at beginning of period, common equity at Jun. 30, 2022			0	14,737	1,465	(1,930)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Return of capital to parent				(1,000)
Employee benefit plans				2
Net income	161				161
Other comprehensive loss, net of tax	(667)					(667)
Balance at end of period, common equity at Sep. 30, 2022	12,768		$ 0	$ 13,739	$ 1,626	$ (2,597)
Balance at end of period at Sep. 30, 2022	$ 14,033	$ 1,265