LOAN SALES AND SECURITIZATIONS - Residential Mortgage Portfolio, MSRs Amortization Method Key Assumptions (Details) - Amortization method - Residential Mortgage - USD ($) $ in Millions |
3 Months Ended | 12 Months Ended |
|---|---|---|
Sep. 30, 2018 |
Dec. 31, 2017 |
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| Servicing Asset at Amortized Cost [Line Items] | ||
| Constant prepayment rate (annualized), actual | 8.10% | 8.30% |
| Constant prepayment rate (annualized), 10% adverse change | $ 0 | $ 0 |
| Constant prepayment rate (annualized), 20% adverse change | $ 0 | $ 0 |
| Spread over forward interest rate swap rates, actual | 9.41% | 10.49% |
| Spread over forward interest rate swap rates, 10% adverse change | $ 0 | $ 0 |
| Spread over forward interest rate swap rates, 20% adverse change | $ 0 | $ 0 |
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- Definition The hypothetical financial impact of a 10 percent adverse change of the discount rate on the fair value of transferor's interests in transferred financial assets (including any servicing assets or servicing liabilities) as of the balance sheet date. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition The hypothetical financial impact of a 10 percent adverse change of prepayment speed on the fair value of transferor's interests in transferred financial assets (including any servicing assets or servicing liabilities) as of the balance sheet date. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition The hypothetical financial impact of a 20 percent adverse change of the discount rate on the fair value of transferor's interests in transferred financial assets (including any servicing assets or servicing liabilities) as of the balance sheet date. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition The hypothetical financial impact of a 20 percent adverse change of prepayment speed on the fair value of transferor's interests in transferred financial assets (including any servicing assets or servicing liabilities) as of the balance sheet date. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Discount rate used to estimate the fair value of servicing assets and servicing liabilities. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Estimated rate of prepayments of principal on servicing assets and servicing liabilities. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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