Business Combinations - Narrative (Details) $ in Millions			8 Months Ended	12 Months Ended
	May 09, 2023 USD ($)	May 01, 2023 USD ($) agreement	Dec. 31, 2023 USD ($)	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Mar. 16, 2023 USD ($)
Business Acquisition [Line Items]
Estimated bargain purchase gain				$ 2,775	$ 0	$ 0
Deposits with banks			$ 595,085	595,085	539,537
Provision for credit losses				9,320	$ 6,389	$ (9,256)
First Republic
Business Acquisition [Line Items]
Deposits with banks							$ 5,000
First Republic | Consortium of large U.S. banks
Business Acquisition [Line Items]
Deposits with banks							$ 30,000
First Republic
Business Acquisition [Line Items]
Estimated bargain purchase gain		$ 2,700	2,775	2,800
Increase to estimated bargain purchase gain				63
Number of shared-loss agreements | agreement		2
Consideration transferred, effective settlement of deposit			5,000
Settlement of securities financing transaction			447
Consideration transferred, amounts payable			3,600
Net income attributable to the acquisition since the acquisition date				4,100
Provision for credit losses		$ 1,200
First Republic | Noninterest revenue
Business Acquisition [Line Items]
Revenue attributable to the acquisition since the acquisition date				4,400
First Republic | Net interest income
Business Acquisition [Line Items]
Revenue attributable to the acquisition since the acquisition date				$ 3,700
First Republic | Core deposits
Business Acquisition [Line Items]
Intangible assets acquired			1,300
Estimated period of future cash flows		7 years
First Republic | Customer relationships
Business Acquisition [Line Items]
Intangible assets acquired			$ 180
Estimated period of future cash flows		7 years
First Republic | Consortium of large U.S. banks
Business Acquisition [Line Items]
Deposits repaid	$ 25,000
First Republic | Purchase Money Note
Business Acquisition [Line Items]
Term of FDIC Purchase Money Note		5 years
Face amount of notes		$ 50,000
Fixed rate of FDCI Purchase Money Note		3.40%
First Republic | Commercial loans and other real estate
Business Acquisition [Line Items]
Percentage of credit losses covered under shared-loss agreement		80.00%
Term of shared-loss agreement		5 years
Recover period for shared-loss agreement		3 years
First Republic | Secured by mortgages on real property or cooperative shares that are a primary residence
Business Acquisition [Line Items]
Percentage of credit losses covered under shared-loss agreement		80.00%
Term of shared-loss agreement		7 years