SECURITIES - Other than temporary impairment recognized in earnings (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Investments, Debt and Equity Securities [Abstract]
Total other-than-temporary impairment losses	$ (2)	$ (7)	$ (7)
Portions of loss recognized in other comprehensive income (before taxes)	0	4	0
Net securities impairment losses recognized in earnings on debt securities	$ (2)	$ (3)	$ (7)

The amount by which the fair value of an investment is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income.

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-Name Accounting Standards Codification
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Amount of other-than-temporary impairment (OTTI) on investment in debt security, recognized in earnings.

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Amount before tax of other than temporary impairment loss (OTTI) on investments in available-for-sale and held-to-maturity debt securities, recognized in other comprehensive loss and attributable to parent entity.

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