Loans - Narrative (Details) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2024 USD ($)	Sep. 30, 2023 USD ($)	Sep. 30, 2024 USD ($) loan_segment	Sep. 30, 2023 USD ($)
Receivables [Abstract]
Number of portfolio segments \| loan_segment			3
Net gains/(losses) on sales of loans and lending-related commitments	$ 65	$ 9	$ 125	$ 46
Net gains/(losses) on sales of loans	$ 47	$ 9	$ 80	$ 52

The net gain (loss) resulting from a sale of loans, including adjustments to record loans classified as held-for-sale at the lower-of-cost-or-market and fair value adjustments to loan held for investment purposes.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 45
-Paragraph 28
-Subparagraph (b)
-SubTopic 10
-Topic 230
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-28

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04(13)(h))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478524/942-220-S99-1

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