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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	Mar. 31, 2025	Dec. 31, 2024
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Securities held to maturity	$ 10,361	$ 10,456
Carrying Value | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	486,202	470,249
Carrying Value | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Non-marketable equity securities held in other financial institutions	71,754	71,643
Accrued interest and loan fees receivable	37,113	38,901
Deposits	8,338,412	8,223,120
FHLB advances, repurchase agreements and other borrowings	12,488	12,460
Subordinated indebtedness	89,599	159,943
Accrued interest payable	6,641	8,033
Carrying Value | Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Securities held to maturity	11,094	11,095
LHFI, net	7,493,515	7,482,653
Estimated Fair Value | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	486,202	470,249
Estimated Fair Value | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Non-marketable equity securities held in other financial institutions	71,754	71,643
Accrued interest and loan fees receivable	37,113	38,901
Deposits	8,332,720	8,217,564
FHLB advances, repurchase agreements and other borrowings	12,340	12,203
Subordinated indebtedness	89,598	159,928
Accrued interest payable	6,641	8,033
Estimated Fair Value | Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Securities held to maturity	10,361	10,456
LHFI, net	$ 7,311,032	$ 7,209,866

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