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Derivative Financial Instruments and Hedging Activities - Narrative (Details) | Sep. 30, 2023 USD ($) derivative_instrument | Dec. 31, 2022 USD ($)
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Derivative [Line Items] |  |
Securities AFS, at estimated fair value | $ 1,335,560,000 | $ 1,299,014,000
Cash collateral received from counterparties under master netting agreements | 109,514,000 | $ 82,135,000
Fair Value Hedging |  |
Derivative [Line Items] |  |
Securities AFS, at estimated fair value | $ 609,100,000 |
Interest Rate Swap | Designated as Hedging Instrument |  |
Derivative [Line Items] |  |
Number of instruments terminated | derivative_instrument | 1 |
Interest Rate Swap | Cash Flow Hedging |  |
Derivative [Line Items] |  |
Derivative, Notional Amount | $ 760,000,000 |

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