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INVESTMENTS - Gross Proceeds from AFS debt securities (Details) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Investments, Debt and Equity Securities [Abstract] |  |  |
Gross proceeds from sales | $ 93 | $ 76 | $ 54
Gross proceeds from maturities | 131 | 83 | 47
Total | $ 224 | $ 159 | $ 101

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- Definition Debt Securities, Available-For-Sale, Gross Proceeds From Maturity + References No definition available. + Details
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- Definition Debt Securities, Available-For-Sale, Gross Proceeds From Sales + References No definition available. + Details
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- Definition Amount of realized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), investment in debt security measured at amortized cost (held-to-maturity) and investment in debt security measured at fair value with change in fair value recognized in net income (trading). + References No definition available. + Details
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- References No definition available. + Details
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