Derivative Financial Instruments and Hedging Activities - Narrative (Details)	Sep. 30, 2023 USD ($) derivative_instrument	Dec. 31, 2022 USD ($)
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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- Definition

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

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Amount of obligation to return cash collateral under master netting arrangements offset against derivative assets.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Nominal or face amount used to calculate payment on derivative.

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