VARIABLE INTEREST ENTITIES - Income Statement Effect (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Provision for income taxes:
Amortization of LIHTC investments under proportional method	$ 4	$ 3
Low-income housing tax credits	(4)	(3)
Other tax benefits related to tax credit investments	(1)	(1)
Total impact on provision for income taxes	$ (1)	$ (1)

Amortization Method Qualified Affordable Housing Project Investments, Low Income Housing Tax Credit

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Amortization Method Qualified Affordable Housing Project Investments, Other Tax Benefits Related to Tax Credit Investments

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Amortization Method Qualified Affordable Housing Project Investments, Provision For Income Tax

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Low Income Tax Credits, Provision For Income Taxes [Abstract]

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Proportional Amortization Method Qualified Affordable Housing Project Investments, Amortization

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