Derivative Financial Instruments - Effect on the Condensed Consolidated Statements of Operations (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Effect of derivative financial instruments on the condensed consolidated financial statements of operations [Abstract]
Derivative loss recognized in OCI	$ (527)	$ 0	$ (940)	$ 0
Derivative loss reclassified from AOCI into income	(72)	0	(224)	0
Fair Value Hedging \| Interest Rate Cap
Effect of derivative financial instruments on the condensed consolidated financial statements of operations [Abstract]
Derivative loss recognized in OCI	(25)	0	(438)	0
Derivative loss reclassified from AOCI into income	(55)	0	(207)	0
Derivative, gain (loss) recognized in income	2,611	6,173	3,082	17,797
Fair Value Hedging \| us-gaap_InterestRateCapMember
Effect of derivative financial instruments on the condensed consolidated financial statements of operations [Abstract]
Derivative loss recognized in OCI	(25)	0	(438)	0
Derivative loss reclassified from AOCI into income	(55)	0	(207)	0
Derivative, gain (loss) recognized in income	39	0	286	0
Fair Value Hedging \| Installment \| Interest Rate Cap
Effect of derivative financial instruments on the condensed consolidated financial statements of operations [Abstract]
Derivative loss recognized in OCI	0	0	0	0
Derivative loss reclassified from AOCI into income	0	0	0	0
Derivative, gain (loss) recognized in income	$ 0	$ 0	$ (14)	$ 0
Fair Value Hedging \| Fixed Income Interest Rate \| Interest Rate Swap, Noncommercial
Effect of derivative financial instruments on the condensed consolidated financial statements of operations [Abstract]
Derivative, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Tax-exempt	Tax-exempt	Tax-exempt	Tax-exempt
Derivative, gain (loss) recognized in income	$ 926	$ 5,881	$ 550	$ 16,929
Fair Value Hedging \| Fixed Income Interest Rate \| Commercial \| Interest Rate Swap
Effect of derivative financial instruments on the condensed consolidated financial statements of operations [Abstract]
Derivative, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Interest and fees on loans	Interest and fees on loans	Interest and fees on loans	Interest and fees on loans
Derivative, gain (loss) recognized in income	$ 96	$ 292	$ 113	$ 868
Fair Value Hedging \| Fixed Income Interest Rate \| Installment \| Interest Rate Swap
Effect of derivative financial instruments on the condensed consolidated financial statements of operations [Abstract]
Derivative, gain (loss) recognized in income	765	0	1,362	0
Fair Value Hedging \| Fixed Income Interest Rate \| Mortgage \| Interest Rate Swap
Effect of derivative financial instruments on the condensed consolidated financial statements of operations [Abstract]
Derivative, gain (loss) recognized in income	785	0	785	0
Cash Flow Hedging \| Commercial \| Interest Rate Floor
Effect of derivative financial instruments on the condensed consolidated financial statements of operations [Abstract]
Derivative loss recognized in OCI	(502)	0	(502)	0
Derivative loss reclassified from AOCI into income	(17)	0	(17)	0
Derivative, gain (loss) recognized in income	(17)	0	(17)	0
Derivatives not designated as hedging instruments
Effect of derivative financial instruments on the condensed consolidated financial statements of operations [Abstract]
Derivative, gain (loss) recognized in income	$ 91	$ 316	$ 1,073	$ (4,930)
Derivatives not designated as hedging instruments \| Interest Rate Cap
Effect of derivative financial instruments on the condensed consolidated financial statements of operations [Abstract]
Derivative, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Interest Expense	Interest Expense	Interest Expense	Interest Expense
Derivative, gain (loss) recognized in income	$ 0	$ 0	$ 0	$ 245
Derivatives not designated as hedging instruments \| Interest Rate Lock Commitments
Effect of derivative financial instruments on the condensed consolidated financial statements of operations [Abstract]
Derivative, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Mortgage loans	Mortgage loans	Mortgage loans	Mortgage loans
Derivative, gain (loss) recognized in income	$ (147)	$ (1,284)	$ 916	$ (8,496)
Derivatives not designated as hedging instruments \| Mandatory Commitments to Sell Mortgage Loans
Effect of derivative financial instruments on the condensed consolidated financial statements of operations [Abstract]
Derivative, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Mortgage loans	Mortgage loans	Mortgage loans	Mortgage loans
Derivative, gain (loss) recognized in income	$ 238	$ 2,250	$ 169	$ 2,874
Derivatives not designated as hedging instruments \| Interest Rate Swaption
Effect of derivative financial instruments on the condensed consolidated financial statements of operations [Abstract]
Derivative, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]			Mortgage loans	Mortgage loans
Derivative, gain (loss) recognized in income	$ 0	$ 0	$ 0	$ (186)
Derivatives not designated as hedging instruments \| Fixed Income Interest Rate \| Commercial \| Interest Rate Swap
Effect of derivative financial instruments on the condensed consolidated financial statements of operations [Abstract]
Derivative, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Interest income	Interest income	Interest income	Interest income
Derivative, gain (loss) recognized in income	$ 5,579	$ 9,015	$ 4,694	$ 23,739
Derivatives not designated as hedging instruments \| Fixed Income Interest Rate \| Mortgage \| Interest Rate Swap
Effect of derivative financial instruments on the condensed consolidated financial statements of operations [Abstract]
Derivative, gain (loss) recognized in income	0	(650)	0	633
Derivatives not designated as hedging instruments \| Variable Income Interest Rate \| Interest Rate Swap
Effect of derivative financial instruments on the condensed consolidated financial statements of operations [Abstract]
Derivative, gain (loss) recognized in income	$ 0	$ 0	$ (12)	$ 0
Derivatives not designated as hedging instruments \| Variable Income Interest Rate \| Commercial \| Interest Rate Swap
Effect of derivative financial instruments on the condensed consolidated financial statements of operations [Abstract]
Derivative, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Interest income	Interest income	Interest income	Interest income
Derivative, gain (loss) recognized in income	$ (5,579)	$ (9,015)	$ (4,694)	$ (23,739)

Effect of derivative financial instruments on the condensed consolidated financial statements of operations [Abstract]

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- Definition

Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4A
-Subparagraph (b)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480434/815-10-50-4A

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- Definition

Indicates line item in statement of income or comprehensive income that includes gain (loss) from derivative.

+ References

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- Definition

Amount, before tax and reclassification, of gain (loss) from derivative instrument designated and qualifying cash flow hedge included in assessment of hedge effectiveness.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 11
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482790/220-10-45-11

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4C
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480434/815-10-50-4C

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480627/815-20-45-3

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4A
-Subparagraph (b)(2)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480434/815-10-50-4A

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 10A
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482790/220-10-45-10A

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- Definition

Amount, before tax, of reclassification of gain (loss) from accumulated other comprehensive income (AOCI) for derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

+ References

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