LOAN SALES AND SECURITIZATIONS - Automobile Loans, MSRs Amortization Method (Details) - USD ($) $ in Millions |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2017 |
Dec. 31, 2016 |
Dec. 31, 2015 |
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| Servicing Asset at Amortized Cost, Balance [Roll Forward] | |||
| Fair value, end of year | $ 238 | $ 226 | |
| Automobile | |||
| Servicing Asset at Amortized Cost, Balance [Roll Forward] | |||
| Carrying value, beginning of year | 18 | 9 | |
| New servicing assets created | $ 11 | ||
| Amortization and other | (10) | (6) | |
| Carrying value, end of year | 8 | 18 | $ 9 |
| Fair value, end of year | $ 9 | $ 18 | |
| Automobile | Sensitivity Analysis Amortization Carrying Method | |||
| Servicing Asset at Amortized Cost, Balance [Roll Forward] | |||
| Weighted-average life (years) | 3 years 6 months | 4 years 2 months | |
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- Definition Weighted average life of securitized assets regardless of when the transfer occurred, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amortized amount of contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of additions from purchases, assumption or transfer to contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of amortization of contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. No definition available.
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- Definition Fair value of contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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