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Fair Value of Financial Instruments - Carrying Value and Estimated Fair Values of Financial Instruments Not Measured at Fair Value (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Securities held to maturity	$ 10,848	$ 11,970
Carrying Value | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	280,441	358,972
Carrying Value | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Non-marketable equity securities held in other financial institutions	55,190	67,378
GNMA repurchase asset	0	24,569
Accrued interest and loan fees receivable	41,688	38,136
Deposits	8,251,125	7,775,702
FHLB advances and other borrowings	83,598	639,230
Subordinated indebtedness	194,279	201,765
Accrued interest payable	12,272	3,917
Carrying Value | Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Securities held to maturity	11,615	11,275
LHFI, net	7,564,076	7,002,861
Estimated Fair Value | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	280,441	358,972
Estimated Fair Value | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Non-marketable equity securities held in other financial institutions	55,190	67,378
GNMA repurchase asset	0	24,569
Accrued interest and loan fees receivable	41,688	38,136
Deposits	8,240,520	7,753,966
FHLB advances and other borrowings	83,187	639,103
Subordinated indebtedness	186,251	181,624
Accrued interest payable	12,272	3,917
Estimated Fair Value | Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Securities held to maturity	10,848	11,970
LHFI, net	$ 7,177,720	$ 6,835,770

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- Definition

Government National Mortgage Association Repurchase Asset

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Junior Subordinated Debenture Owed to Unconsolidated Subsidiary Trust, Fair Value

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- Definition

Fair value portion of accrued expenses.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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-Publisher FASB
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Fair value of investment in debt security measured at amortized cost (held-to-maturity).

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(1))
-Publisher FASB
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
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-Name Accounting Standards Codification
-Section 50
-Paragraph 5A
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-5A

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
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-Publisher FASB
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