Fair Value of Financial Instruments - Carrying Value and Estimated Fair Values of Financial Instruments Not Measured at Fair Value (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Securities held to maturity	$ 9,074	$ 9,607
Carrying Value \| Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	546,531	424,217
Carrying Value \| Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Non-marketable equity securities held in other financial institutions	37,662	31,069
Loans held for sale	1,146	1,032
Accrued interest receivable	35,748	35,152
Deposits	8,703,251	8,307,247
FHLB advances, repurchase agreements and other borrowings	136,878	19,050
Subordinated indebtedness	16,594	16,544
Accrued interest payable	2,811	3,239
Carrying Value \| Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Securities held to maturity	10,557	10,559
LHFI, net	7,975,389	7,574,135
Estimated Fair Value \| Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	546,531	424,217
Estimated Fair Value \| Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Non-marketable equity securities held in other financial institutions	37,662	31,069
Loans held for sale	1,146	1,032
Accrued interest receivable	35,748	35,152
Deposits	8,698,766	8,302,897
FHLB advances, repurchase agreements and other borrowings	136,827	18,989
Subordinated indebtedness	16,580	16,530
Accrued interest payable	2,811	3,239
Estimated Fair Value \| Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Securities held to maturity	9,074	9,607
LHFI, net	$ 7,868,185	$ 7,459,710

Accrued Interest Receivable, Fair Value

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- Definition

Federal Home Loan Bank Advances and Securities Sold Under Agreements to Repurchase, Fair Value

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Junior Subordinated Debenture Owed to Unconsolidated Subsidiary Trust, Fair Value

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Loans and Leases Receivable, Net of Deferred Income, Fair Value Disclosure

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Other Investments, Fair Value

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Fair value portion of accrued expenses.

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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Fair value portion of deposit liabilities held by the entity, including, but not limited to, foreign and domestic, interest and noninterest bearing, demand deposits, saving deposits, negotiable orders of withdrawal (NOW) and time deposits.

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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.

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Fair value of investment in debt security measured at amortized cost (held-to-maturity).

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Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

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