Loans - Commercial Banking: Risk Profile by Internal Risk Rating (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Financing Receivable, Allowance for Credit Loss [Line Items]
Total loans held for investment	$ 320,472	$ 312,331
Commercial Banking:
Financing Receivable, Allowance for Credit Loss [Line Items]
2023	10,556	20,217
2022	18,879	14,024
2021	11,282	6,570
2020	5,124	7,420
2019	5,444	4,431
Prior	10,271	10,374
Total Term Loans	61,556	63,036
Revolving Loans	28,740	31,594
Revolving Loans Converted to Term	192	46
Total loans held for investment	90,488	94,676
Commercial Banking: | Commercial and multifamily real estate
Financing Receivable, Allowance for Credit Loss [Line Items]
2023	3,281	6,220
2022	6,185	5,316
2021	3,603	1,888
2020	1,303	3,508
2019	2,614	2,324
Prior	4,737	4,805
Total Term Loans	21,723	24,061
Revolving Loans	12,698	13,367
Revolving Loans Converted to Term	25	25
Total loans held for investment	34,446	37,453
Commercial Banking: | Commercial and multifamily real estate | Noncriticized
Financing Receivable, Allowance for Credit Loss [Line Items]
2023	3,068	5,860
2022	4,665	4,807
2021	2,773	1,676
2020	1,019	2,879
2019	2,104	1,927
Prior	3,670	3,474
Total Term Loans	17,299	20,623
Revolving Loans	12,565	13,254
Revolving Loans Converted to Term	25	25
Total loans held for investment	29,889	33,902
Commercial Banking: | Commercial and multifamily real estate | Criticized | Criticized performing
Financing Receivable, Allowance for Credit Loss [Line Items]
2023	148	359
2022	1,494	487
2021	706	212
2020	284	535
2019	463	378
Prior	904	1,196
Total Term Loans	3,999	3,167
Revolving Loans	133	113
Revolving Loans Converted to Term	0	0
Total loans held for investment	4,132	3,280
Commercial Banking: | Commercial and multifamily real estate | Criticized | Criticized nonperforming
Financing Receivable, Allowance for Credit Loss [Line Items]
2023	65	1
2022	26	22
2021	124	0
2020	0	94
2019	47	19
Prior	163	135
Total Term Loans	425	271
Revolving Loans	0	0
Revolving Loans Converted to Term	0	0
Total loans held for investment	425	271
Commercial Banking: | Commercial and industrial
Financing Receivable, Allowance for Credit Loss [Line Items]
2023	7,275	13,997
2022	12,694	8,708
2021	7,679	4,682
2020	3,821	3,912
2019	2,830	2,107
Prior	5,534	5,569
Total Term Loans	39,833	38,975
Revolving Loans	16,042	18,227
Revolving Loans Converted to Term	167	21
Total loans held for investment	56,042	57,223
Commercial Banking: | Commercial and industrial | Noncriticized
Financing Receivable, Allowance for Credit Loss [Line Items]
2023	6,909	13,485
2022	11,935	7,993
2021	6,994	4,466
2020	3,566	3,420
2019	2,359	1,797
Prior	5,117	5,349
Total Term Loans	36,880	36,510
Revolving Loans	14,822	17,187
Revolving Loans Converted to Term	167	21
Total loans held for investment	51,869	53,718
Commercial Banking: | Commercial and industrial | Criticized | Criticized performing
Financing Receivable, Allowance for Credit Loss [Line Items]
2023	353	482
2022	706	686
2021	655	216
2020	237	336
2019	348	228
Prior	349	163
Total Term Loans	2,648	2,111
Revolving Loans	1,189	964
Revolving Loans Converted to Term	0	0
Total loans held for investment	3,837	3,075
Commercial Banking: | Commercial and industrial | Criticized | Criticized nonperforming
Financing Receivable, Allowance for Credit Loss [Line Items]
2023	13	30
2022	53	29
2021	30	0
2020	18	156
2019	123	82
Prior	68	57
Total Term Loans	305	354
Revolving Loans	31	76
Revolving Loans Converted to Term	0	0
Total loans held for investment	$ 336	$ 430