Fair Value Disclosures - Summary of the Carrying Amounts and Estimated Fair Values of Financial Instruments (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available-for-sale debt securities	$ 3,225,892	$ 2,615,644
Held-to-maturity debt securities	865,477	935,514
Equity securities	51,825	33,956
Derivative assets	32,944	13,504
Long-term debt	859,147	931,442
Derivative liabilities	70,917	91,758
Carrying Amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	3,242,850	5,012,260
Available-for-sale debt securities	3,225,892	2,615,644
Held-to-maturity debt securities	865,477	935,514
Equity securities	51,825	33,956
Loans held for sale	44,105	36,357
Loans held for investment, net	20,090,585	19,033,871
Derivative assets	32,944	13,504
Total deposits	22,371,839	22,856,880
Short-term borrowings	1,500,000	1,201,142
Long-term debt	859,147	931,442
Securities sold not yet purchased	10,602
Derivative liabilities	70,917	91,758
Estimated Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	3,242,850	5,012,260
Available-for-sale debt securities	3,225,892	2,615,644
Held-to-maturity debt securities	763,844	816,914
Equity securities	51,825	33,956
Loans held for sale	44,105	36,357
Loans held for investment, net	20,050,974	18,969,922
Derivative assets	32,944	13,504
Total deposits	22,379,452	22,857,949
Short-term borrowings	1,500,000	1,201,142
Long-term debt	801,309	881,716
Securities sold not yet purchased	10,602
Derivative liabilities	70,917	91,758
Level 1 | Estimated Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	3,242,850	5,012,260
Available-for-sale debt securities	636,473	670,582
Held-to-maturity debt securities	0	0
Equity securities	40,661	22,879
Loans held for sale	15,000	0
Loans held for investment, net	0	0
Derivative assets	0	0
Total deposits	0	0
Short-term borrowings	0	0
Long-term debt	0	0
Securities sold not yet purchased	10,602
Derivative liabilities	0	0
Level 2 | Estimated Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	0	0
Available-for-sale debt securities	2,577,424	1,933,201
Held-to-maturity debt securities	763,844	816,914
Equity securities	11,164	11,077
Loans held for sale	29,105	0
Loans held for investment, net	0	0
Derivative assets	32,944	13,504
Total deposits	0	0
Short-term borrowings	1,500,000	1,201,142
Long-term debt	801,309	881,716
Securities sold not yet purchased	0
Derivative liabilities	70,917	91,758
Level 3 | Estimated Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	0	0
Available-for-sale debt securities	11,995	11,861
Held-to-maturity debt securities	0	0
Equity securities	0	0
Loans held for sale	0	36,357
Loans held for investment, net	20,050,974	18,969,922
Derivative assets	0	0
Total deposits	22,379,452	22,857,949
Short-term borrowings	0	0
Long-term debt	0	0
Securities sold not yet purchased	0
Derivative liabilities	$ 0	$ 0