Fair Value Disclosures - Schedule of Estimated Fair Values of the Company’s Financial Instruments (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025
Financial Assets:
Available for sale	$ 6,741,573	$ 6,372,463
Held to maturity	1,528	1,689
Equity	48,174	48,200
Net loans held for investment	11,382,681	11,284,931
Carrying amount
Financial Assets:
Available for sale	6,741,573	6,372,463
Held to maturity	1,528	1,689
Equity	48,174	48,200
Net loans held for investment	11,382,681	11,284,931
Loans held for sale	29,457	54,119
Derivatives	7,732	7,969
Total assets	19,589,273	19,834,553
Financial Liabilities
Federal funds purchased and customer repurchase agreements	1,066,923	1,011,851
Accrued interest payable	8,279	9,306
Derivatives	6,284	7,021
Cash and due from banks | Carrying amount
Financial Assets:
Cash and due from banks	190,868	258,588
Short-term interest-bearing deposits | Carrying amount
Financial Assets:
Cash and due from banks	1,185,077	1,805,215
Interest-bearing deposits | Carrying amount
Financial Assets:
Cash and due from banks	750	1,039
Federal funds sold and securities purchased under agreements to resell | Carrying amount
Financial Assets:
Cash and due from banks	1,433	340
Level 1 | Estimated Fair Value
Financial Assets:
Available for sale	1,097,918	929,305
Held to maturity	0	0
Equity	0	0
Net loans held for investment	0	0
Loans held for sale	0	0
Derivatives	0	0
Total assets	2,476,045	2,993,448
Financial Liabilities
Federal funds purchased and customer repurchase agreements	1,066,923	1,011,851
Accrued interest payable	8,279	9,306
Derivatives	0	0
Level 1 | Cash and due from banks | Estimated Fair Value
Financial Assets:
Cash and due from banks	190,868	258,588
Level 1 | Short-term interest-bearing deposits | Estimated Fair Value
Financial Assets:
Cash and due from banks	1,185,077	1,805,215
Level 1 | Interest-bearing deposits | Estimated Fair Value
Financial Assets:
Cash and due from banks	750	0
Level 1 | Federal funds sold and securities purchased under agreements to resell | Estimated Fair Value
Financial Assets:
Cash and due from banks	1,433	340
Level 2 | Estimated Fair Value
Financial Assets:
Available for sale	5,643,654	5,443,158
Held to maturity	862	1,023
Equity	36,661	36,690
Net loans held for investment	0	0
Loans held for sale	29,457	54,119
Derivatives	7,732	7,969
Total assets	5,718,366	5,542,960
Financial Liabilities
Federal funds purchased and customer repurchase agreements	0	0
Accrued interest payable	0	0
Derivatives	6,284	7,021
Level 2 | Cash and due from banks | Estimated Fair Value
Financial Assets:
Cash and due from banks	0	0
Level 2 | Short-term interest-bearing deposits | Estimated Fair Value
Financial Assets:
Cash and due from banks	0	0
Level 2 | Interest-bearing deposits | Estimated Fair Value
Financial Assets:
Cash and due from banks	0	0
Level 2 | Federal funds sold and securities purchased under agreements to resell | Estimated Fair Value
Financial Assets:
Cash and due from banks	0	0
Level 3 | Estimated Fair Value
Financial Assets:
Available for sale	0	0
Held to maturity	677	677
Equity	11,513	11,510
Net loans held for investment	11,364,316	11,285,348
Loans held for sale	0	0
Derivatives	0	0
Total assets	11,376,506	11,298,574
Financial Liabilities
Federal funds purchased and customer repurchase agreements	0	0
Accrued interest payable	0	0
Derivatives	0	0
Level 3 | Cash and due from banks | Estimated Fair Value
Financial Assets:
Cash and due from banks	0	0
Level 3 | Short-term interest-bearing deposits | Estimated Fair Value
Financial Assets:
Cash and due from banks	0	0
Level 3 | Interest-bearing deposits | Estimated Fair Value
Financial Assets:
Cash and due from banks	0	1,039
Level 3 | Federal funds sold and securities purchased under agreements to resell | Estimated Fair Value
Financial Assets:
Cash and due from banks	$ 0	$ 0