BORROWINGS - Summary of Long-Term Borrowings (Detail) - USD ($) $ in Millions	Jun. 30, 2021	Dec. 31, 2020
Debt Disclosure [Abstract]
Federal Home Loan Bank advances	$ 200	$ 400
Senior notes	299	299
Subordinated notes	75	81
Junior subordinated debt	66	66
Other subordinated debt	248	249
Total long-term borrowings	$ 888	$ 1,095

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Including both current and noncurrent portions, Federal Home Loan Bank borrowings initially due beyond one year or beyond the normal operating cycle if longer.

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Including the current and noncurrent portions, the carrying value of junior subordinated long-term debt owed to unconsolidated subsidiary trusts as of the balance sheet date. Such debt places a lender in a lien position behind debt having a higher priority of repayment in liquidation of the entity's assets and was initially scheduled to be repaid after one year or beyond the normal operating cycle if longer.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Including the current and noncurrent portions, carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer). Senior note holders are paid off in full before any payments are made to junior note holders.

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Carrying value as of the balance sheet date of collateralized/uncollateralized debt obligation (with maturities initially due after one year or beyond the operating cycle if longer), excluding current portion. Subordinated debt places a lender in a lien position behind the primary lender of the company.

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