Equity - Narrative (Details)		1 Months Ended		12 Months Ended
	May 04, 2020 shares	Aug. 31, 2019 $ / shares shares	Feb. 28, 2019 USD ($) shares	Dec. 31, 2021 USD ($) employeeStockOwnershipPlan shares	Dec. 31, 2020 USD ($) shares	Dec. 31, 2019 USD ($) shares		Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Equity, Class of Treasury Stock [Line Items]
Shares repurchased | shares				0	0	213,000,000	[1]
Amount of remaining shares authorized in stock purchase plan, value				$ 5,300,000,000
Preferred stock, shares outstanding | shares	0			0	0
Number of employee stock ownership plans | employeeStockOwnershipPlan				1
Common Stock [Member]
Equity, Class of Treasury Stock [Line Items]
Shares issued upon conversion of convertible preferred stock (in shares) | shares	1,070,369
Common ESOP Plan [Member]
Equity, Class of Treasury Stock [Line Items]
ESOP compensation expense				$ 19,000,000	$ 19,000,000	$ 20,000,000
December 2017 Stock Purchase Plan [Member]
Equity, Class of Treasury Stock [Line Items]
Amount of shares authorized in stock purchase plan, value									$ 10,000,000,000
December 2018 Stock Purchase Plan [Member]
Equity, Class of Treasury Stock [Line Items]
Amount of shares authorized in stock purchase plan, value								$ 10,000,000,000
Share Repurchase Agreement with Goldman, Sachs & Co. LLC [Member]
Equity, Class of Treasury Stock [Line Items]
Amount of shares authorized in stock purchase plan, value			$ 6,800,000,000
Accelerated share repurchases, cash paid			$ 6,800,000,000
Shares repurchased | shares		33,500,000	130,000,000
Accelerated share repurchase, percentage of agreement			80.00%
Accelerated share repurchase, final average price paid (in dollars per share) | $ / shares		$ 41.42

[1] Represents shares purchased pursuant to the ASR with Goldman Sachs & Co. LLC entered into in February 2019, as well as open market share repurchases of $2.1 billion