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v3.26.1

Debt - Narrative (Details) $ in Millions | 6 Months Ended |
--- | --- | ---
Jun. 30, 2026 USD ($) class subsidiaryBusinessTrust | Dec. 31, 2025 USD ($)
Debt Instrument [Line Items] |  |
Number of classes of financial instruments | class | 2 |
Number of business subsidiary trusts | subsidiaryBusinessTrust | 2 |
Interest Rate Swap |  |
Debt Instrument [Line Items] |  |
Amount of hedged item | $ 20 |
ACST II | Junior Subordinated Debt, Preferred Securities |  |
Debt Instrument [Line Items] |  |
Basis spread on variable rate (in percent) | 3.15% |
ACST III |  |
Debt Instrument [Line Items] |  |
Basis spread on variable rate (in percent) | 2.00% |
Federal Reserve Bank Advances |  |
Debt Instrument [Line Items] |  |
Collateral, at carrying cost | $ 938 | $ 707
Collateral, at fair value | 683 | 707
Federal Home Loan Bank of New York |  |
Debt Instrument [Line Items] |  |
Collateral, at carrying cost | 1,100 | 948
Collateral, at fair value | $ 928 | $ 948

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