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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 ($)		3 Months Ended	12 Months Ended
		Mar. 31, 2024	Dec. 31, 2023
Cash Flow Hedging
Derivative [Line Items]
Derivative, Notional Amount		$ 940,000,000,000
Financial Institution Counterparties | Derivatives designated as non-hedging instruments
Derivative [Line Items]
Derivative, Notional Amount	[1]	$ 245,874,000	$ 248,073,000
Remaining Maturity		7 years 2 months 12 days	7 years 4 months 24 days
Weighted Average Receive Rate		5.81%	5.84%
Weighted Average Pay Rate		2.87%	2.88%
Financial Institution Counterparties | Cash Flow Hedging | Derivatives designated as hedging instruments
Derivative [Line Items]
Derivative, Notional Amount	[1]	$ 940,000,000	$ 1,010,000,000
Remaining Maturity		2 years 3 months 18 days	2 years 3 months 18 days
Weighted Average Receive Rate		5.40%	5.44%
Weighted Average Pay Rate		2.94%	2.65%
Financial Institution Counterparties | Fair Value Hedging | Derivatives designated as hedging instruments
Derivative [Line Items]
Derivative, Notional Amount	[1]	$ 453,440,000	$ 453,440,000
Remaining Maturity		5 years 1 month 6 days	5 years 4 months 24 days
Weighted Average Receive Rate		5.34%	5.37%
Weighted Average Pay Rate		3.13%	3.13%
Customer Counterparties | Derivatives designated as non-hedging instruments
Derivative [Line Items]
Derivative, Notional Amount	[1]	$ 245,874,000	$ 248,073,000
Remaining Maturity		7 years 2 months 12 days	7 years 4 months 24 days
Weighted Average Receive Rate		2.87%	2.88%
Weighted Average Pay Rate		5.81%	5.84%
[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.

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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

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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

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Nominal or face amount used to calculate payment on derivative.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480434/815-10-50-1B

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1A
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480434/815-10-50-1A

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