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Derivative Financial Instruments and Hedging Activities - Weighted Average Remaining Maturity, Lives, and Rates of Interest Rate Swaps (Details) - Interest Rate Swap - USD ($) | 9 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2023 | Dec. 31, 2022
Cash Flow Hedging |  |  |
Derivative [Line Items] |  |  |
Derivative, Notional Amount |  | $ 760,000,000 |
Financial Institution Counterparties | Not Designated as Hedging Instrument |  |  |
Derivative [Line Items] |  |  |
Derivative, Notional Amount | [1] | $ 216,777,000 | $ 223,124,000
Remaining Maturity |  | 8 years 3 months 18 days | 9 years
Weighted Average Receive Rate |  | 5.91% | 4.83%
Weighted Average Pay Rate |  | 2.66% | 2.69%
Financial Institution Counterparties | Cash Flow Hedging | Designated as Hedging Instrument |  |  |
Derivative [Line Items] |  |  |
Derivative, Notional Amount | [1] | $ 760,000,000 | $ 575,000,000
Remaining Maturity |  | 2 years 4 months 24 days | 2 years 3 months 18 days
Weighted Average Receive Rate |  | 5.42% | 4.44%
Weighted Average Pay Rate |  | 2.02% | 1.13%
Financial Institution Counterparties | Fair Value Hedging | Designated as Hedging Instrument |  |  |
Derivative [Line Items] |  |  |
Derivative, Notional Amount | [1] | $ 654,870,000 | $ 742,675,000
Remaining Maturity |  | 5 years 7 months 6 days | 6 years 3 months 18 days
Weighted Average Receive Rate |  | 5.30% | 3.42%
Weighted Average Pay Rate |  | 3.19% | 3.21%
Customer Counterparties | Not Designated as Hedging Instrument |  |  |
Derivative [Line Items] |  |  |
Derivative, Notional Amount | [1] | $ 216,777,000 | $ 223,124,000
Remaining Maturity |  | 8 years 3 months 18 days | 9 years
Weighted Average Receive Rate |  | 2.66% | 2.69%
Weighted Average Pay Rate |  | 5.91% | 4.83%
[1] | Notional amounts, which represent the extent of involvement in the derivatives market, are used to determine the contractual cash flows required in accordance with the terms of the agreement. These amounts are typically not exchanged, significantly exceed amounts subject to credit or market risk and are not reflected in the consolidated balance sheets.

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- Definition Derivative, Weighted Average Pay Rate + References No definition available. + Details
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- Definition Average remaining period until maturity of the derivative contract, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
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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. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 815 -SubTopic 40 -Name Accounting Standards Codification -Section 50 -Paragraph 5 -Subparagraph (f) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480237/815-40-50-5 + Details
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