Consolidated Statements of Changes in Shareholders' Equity - USD ($) shares in Thousands, $ in Millions	Total	Common Stock	Preferred Stock	Additional Paid-In Capital	Retained Earnings	AOCI	Noncontrolling Interests
Beginning balance at Dec. 31, 2018	$ 30,178	$ 3,817	$ 3,053	$ 6,849	$ 18,118	$ (1,715)	$ 56
Beginning balance (in shares) at Dec. 31, 2018		763,326
Add (Deduct):
Net income	798				792		6
OCI	294					294
Stock transactions:
Issued in connection with equity awards, net	(28)	$ 13		(41)
Issued in connection with equity awards, net (in shares)		2,594
Cash dividends declared on common stock	(309)				(309)
Cash dividends declared on preferred stock	(43)				(43)
Equity-based compensation expense	32			32
Other, net	(39)			3	(40)		(2)
Ending balance at Mar. 31, 2019	30,883	$ 3,830	3,053	6,843	18,518	(1,421)	60
Ending balance (in shares) at Mar. 31, 2019		765,920
Beginning balance at Dec. 31, 2019	$ 66,558	$ 6,711	5,102	35,609	19,806	(844)	174
Beginning balance (in shares) at Dec. 31, 2019	1,342,166	1,342,166
Add (Deduct):
Net income	$ 1,063				1,060		3
OCI	1,742					1,742
Stock transactions:
Issued in connection with equity awards, net	(80)	$ 26		(104)	(2)
Issued in connection with equity awards, net (in shares)		5,295
Redemption of preferred stock	(503)		(503)
Cash dividends declared on common stock	(605)				(605)
Cash dividends declared on preferred stock	(74)				(74)
Equity-based compensation expense	79			79
Cumulative effect adjustment for new accounting standards	(2,109)				(2,109)
Other, net	(10)						(10)
Ending balance at Mar. 31, 2020	$ 66,061	$ 6,737	$ 4,599	$ 35,584	$ 18,076	$ 898	$ 167
Ending balance (in shares) at Mar. 31, 2020	1,347,461	1,347,461