MORTGAGE BANKING AND OTHER SERVICED LOANS - Narrative (Details) - USD ($) $ in Billions	9 Months Ended
Sep. 30, 2023	Dec. 31, 2022
Residential mortgages
Accounts, Notes, Loans and Financing Receivable [Line Items]
MSR loans	$ 97.6	$ 96.7
Minimum
Accounts, Notes, Loans and Financing Receivable [Line Items]
Sensitivity analysis, basis spread	10.00%
Maximum
Accounts, Notes, Loans and Financing Receivable [Line Items]
Sensitivity analysis, basis spread	20.00%

Amount, after the effects of master netting arrangements, of funds outstanding borrowed in the form of a security repurchase agreement between the entity and another party for the sale and repurchase of identical or substantially the same securities at a date certain for a specified price. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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+ Details