Investment Securities - Amortized Costs and Estimated Fair Values (Details) - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Available-for-sale securities
Amortized cost	$ 205,456,000,000	$ 216,188,000,000
Unallocated portfolio layer fair value basis adjustments, Amortized cost	73,000,000
Gross unrealized gains	1,762,000,000	890,000,000
Unallocated portfolio layer fair value basis adjustments, Gross unrealized gains	(73,000,000)
Gross unrealized losses	5,514,000,000	11,221,000,000
Fair value	201,704,000,000	205,857,000,000
Held-to-maturity securities
Amortized cost	369,848,000,000	425,305,000,000
Gross unrealized gains	178,000,000	105,000,000
Gross unrealized losses	27,272,000,000	36,762,000,000
Fair value	342,754,000,000	388,648,000,000
Total investment securities, net of allowance for credit losses
Amortized cost	575,304,000,000	641,493,000,000
Gross unrealized gains	1,940,000,000	995,000,000
Gross unrealized losses	32,786,000,000	47,983,000,000
Fair value	544,458,000,000	594,505,000,000
HTM securities purchased	4,100,000,000	33,700,000,000	$ 111,800,000,000
Allowance for credit losses on investment securities	128,000,000	96,000,000	$ 42,000,000
Accrued interest receivables on investment securities	2,800,000,000	2,500,000,000
Accrued interest receivables reversed through interest income on AFS securities	0	0
Accrued interest receivables reversed through interest income on HTM securities	0	0
First Republic
Available-for-sale securities
Fair value	24,200,000,000
Total mortgage-backed securities
Available-for-sale securities
Amortized cost	95,001,000,000	84,059,000,000
Gross unrealized gains	896,000,000	485,000,000
Gross unrealized losses	4,285,000,000	6,463,000,000
Fair value	91,612,000,000	78,081,000,000
Held-to-maturity securities
Amortized cost	125,857,000,000	134,356,000,000
Gross unrealized gains	56,000,000	48,000,000
Gross unrealized losses	13,194,000,000	15,687,000,000
Fair value	112,719,000,000	118,717,000,000
U.S. GSEs and government agencies
Available-for-sale securities
Amortized cost	88,377,000,000	77,194,000,000
Gross unrealized gains	870,000,000	479,000,000
Gross unrealized losses	4,077,000,000	6,170,000,000
Fair value	85,170,000,000	71,503,000,000
Held-to-maturity securities
Amortized cost	105,614,000,000	113,492,000,000
Gross unrealized gains	39,000,000	35,000,000
Gross unrealized losses	11,643,000,000	13,709,000,000
Fair value	94,010,000,000	99,818,000,000
Residential: U.S.
Available-for-sale securities
Amortized cost	2,086,000,000	1,576,000,000
Gross unrealized gains	10,000,000	1,000,000
Gross unrealized losses	68,000,000	111,000,000
Fair value	2,028,000,000	1,466,000,000
Held-to-maturity securities
Amortized cost	9,709,000,000	10,503,000,000
Gross unrealized gains	4,000,000	3,000,000
Gross unrealized losses	970,000,000	1,244,000,000
Fair value	8,743,000,000	9,262,000,000
Residential: Non-U.S.
Available-for-sale securities
Amortized cost	1,608,000,000	3,176,000,000
Gross unrealized gains	4,000,000	5,000,000
Gross unrealized losses	1,000,000	27,000,000
Fair value	1,611,000,000	3,154,000,000
Commercial
Available-for-sale securities
Amortized cost	2,930,000,000	2,113,000,000
Gross unrealized gains	12,000,000	0
Gross unrealized losses	139,000,000	155,000,000
Fair value	2,803,000,000	1,958,000,000
Held-to-maturity securities
Amortized cost	10,534,000,000	10,361,000,000
Gross unrealized gains	13,000,000	10,000,000
Gross unrealized losses	581,000,000	734,000,000
Fair value	9,966,000,000	9,637,000,000
U.S. Treasury and government agencies
Available-for-sale securities
Amortized cost	58,051,000,000	95,217,000,000
Gross unrealized gains	276,000,000	302,000,000
Gross unrealized losses	522,000,000	3,459,000,000
Fair value	57,805,000,000	92,060,000,000
Held-to-maturity securities
Amortized cost	173,666,000,000	207,463,000,000
Gross unrealized gains	0	0
Gross unrealized losses	13,074,000,000	18,363,000,000
Fair value	160,592,000,000	189,100,000,000
Obligations of U.S. states and municipalities
Available-for-sale securities
Amortized cost	21,243,000,000	7,103,000,000
Gross unrealized gains	390,000,000	86,000,000
Gross unrealized losses	266,000,000	403,000,000
Fair value	21,367,000,000	6,786,000,000
Held-to-maturity securities
Amortized cost	9,945,000,000	19,747,000,000
Gross unrealized gains	74,000,000	53,000,000
Gross unrealized losses	591,000,000	1,080,000,000
Fair value	9,428,000,000	18,720,000,000
Non-U.S. government debt securities
Available-for-sale securities
Amortized cost	21,387,000,000	20,360,000,000
Gross unrealized gains	254,000,000	14,000,000
Gross unrealized losses	359,000,000	678,000,000
Fair value	21,282,000,000	19,696,000,000
Corporate debt securities
Available-for-sale securities
Amortized cost	128,000,000	381,000,000
Gross unrealized gains	0	0
Gross unrealized losses	28,000,000	24,000,000
Fair value	100,000,000	357,000,000
Asset-backed securities: Collateralized loan obligations
Available-for-sale securities
Amortized cost	6,769,000,000	5,916,000,000
Gross unrealized gains	11,000,000	1,000,000
Gross unrealized losses	28,000,000	125,000,000
Fair value	6,752,000,000	5,792,000,000
Held-to-maturity securities
Amortized cost	58,565,000,000	61,414,000,000
Gross unrealized gains	47,000,000	4,000,000
Gross unrealized losses	352,000,000	1,522,000,000
Fair value	58,260,000,000	59,896,000,000
Asset-backed securities: Other
Available-for-sale securities
Amortized cost	2,804,000,000	3,152,000,000
Gross unrealized gains	8,000,000	2,000,000
Gross unrealized losses	26,000,000	69,000,000
Fair value	2,786,000,000	3,085,000,000
Held-to-maturity securities
Amortized cost	1,815,000,000	2,325,000,000
Gross unrealized gains	1,000,000	0
Gross unrealized losses	61,000,000	110,000,000
Fair value	$ 1,755,000,000	$ 2,215,000,000