Loans and Allowance for Credit Losses on Loans - Loans Held for Investment by Portfolio Segment (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025	Jun. 30, 2025	Dec. 31, 2024
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 24,947,226	$ 24,040,202
Allowance for credit losses on loans	(268,268)	(270,557)	$ (277,648)	$ (271,709)
Loans held for investment, net	24,678,958	23,769,645
Loans held for sale	0	4,361
Interest receivable	110,700	107,300
Unearned income (net of direct origination costs)	(106,900)	(106,800)
Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	13,006,203	12,163,545
Allowance for credit losses on loans	(221,366)	(202,029)	(207,912)	(198,423)
Mortgage finance
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	6,383,381	6,064,019
Allowance for credit losses on loans	(3,123)	(6,221)	(10,630)	(2,755)
Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	5,128,375	5,378,712
Allowance for credit losses on loans	(41,976)	(60,559)	(57,296)	(68,825)
Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	429,267	433,926
Allowance for credit losses on loans	$ (1,803)	$ (1,748)	$ (1,810)	$ (1,706)

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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