FEDERAL HOME LOAN BANK MEMBERSHIP - Narrative (Details) - Federal Home Loan Bank of New York - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Maximum percentage of admitted assets allowed for borrowing base	10.00%		10.00%
Admitted assets for FHLB	$ 24,000.0		$ 24,000.0
Maximum amount available under FHLB	2,000.0		2,000.0
Outstanding	519.0		519.0
Interest expense	$ 7.0	$ 0.8	$ 13.0	$ 2.0
Amount of borrowed funds required to be used to acquire additional membership stock, percentage			4.50%

Federal Home Loan Bank Advances General Debt Obligations Disclosures Admitted Assets

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Federal Home Loan Bank Advances General Debt Obligations Disclosures Maximum Percentage Of Admitted Assets Allowed For Borrowing Base

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Federal Home Loan Bank Advances Required To Be Used To Acquire Additional Membership Stock Percentage

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Amount of maximum advances or credit lines available from the Federal Home Loan Bank (FHLB).

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Amount of the cost of borrowed funds accounted for as interest expense for debt.

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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