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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	Sep. 30, 2024	Dec. 31, 2023
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Securities held to maturity	$ 10,701	$ 10,848
Carrying Value | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	321,191	280,441
Carrying Value | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Non-marketable equity securities held in other financial institutions	67,068	55,190
Accrued interest and loan fees receivable	42,925	41,688
Deposits	8,486,568	8,251,125
FHLB advances, repurchase agreements and other borrowings	30,446	83,598
Subordinated indebtedness	159,861	194,279
Accrued interest payable	15,510	12,272
Carrying Value | Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Securities held to maturity	11,096	11,615
LHFI, net	7,860,801	7,564,076
Estimated Fair Value | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	321,191	280,441
Estimated Fair Value | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Non-marketable equity securities held in other financial institutions	67,068	55,190
Accrued interest and loan fees receivable	42,925	41,688
Deposits	8,481,684	8,240,520
FHLB advances, repurchase agreements and other borrowings	30,359	83,187
Subordinated indebtedness	159,277	186,251
Accrued interest payable	15,510	12,272
Estimated Fair Value | Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Securities held to maturity	10,701	10,848
LHFI, net	$ 7,547,324	$ 7,177,720

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