Loans and Leases Held for Investment - Loans and Leases Held for Investment (Details) - USD ($) $ in Thousands		Mar. 31, 2026	Dec. 31, 2025	Mar. 31, 2025	Dec. 31, 2024
Financing Receivable, Credit Quality Indicator [Line Items]
Total gross loans and leases HFI		$ 24,883,113	$ 25,155,487
Deferred Discounts, Finance Charges and Interest Included in Receivables	[1]	(67,640)	(86,061)
Financing Receivable, Unamortized Loan Cost (Fee)		(35,126)	(36,747)
Loans and leases HFI		24,780,347	25,032,679	$ 24,126,527
Allowance for loan and lease losses		(241,600)	(245,612)	(234,986)	$ (239,360)
Loans and leases, net	[2]	24,538,747	24,787,067
Land and Acquisitions and Development Loans		217,800	214,500
Financing Receivable, Unamortized Purchase Premium (Discount)		(143,000)	(158,500)
Financing Receivable, Unamortized Purchase Premium		75,400	72,400
Interest Receivable		12,300	11,400
Loans and Finance Receivables [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Interest Receivable		106,200	104,300
Real Estate Mortgage
Financing Receivable, Credit Quality Indicator [Line Items]
Total gross loans and leases HFI		13,584,489	13,846,097
Loans and leases HFI		13,506,898	13,750,787	13,492,658
Allowance for loan and lease losses		(131,514)	(137,401)	(130,116)	(145,754)
Real Estate Construction and Land
Financing Receivable, Credit Quality Indicator [Line Items]
Total gross loans and leases HFI	[3]	1,903,999	1,959,591
Loans and leases HFI		1,892,329	1,947,627	2,861,038
Allowance for loan and lease losses		(10,395)	(8,849)	(14,124)	(10,940)
Commercial
Financing Receivable, Credit Quality Indicator [Line Items]
Total gross loans and leases HFI		9,048,610	8,994,466
Loans and leases HFI		9,032,987	8,977,206	7,378,799
Allowance for loan and lease losses		(86,815)	(86,087)	(75,989)	(67,833)
Consumer
Financing Receivable, Credit Quality Indicator [Line Items]
Total gross loans and leases HFI		346,015	355,333
Loans and leases HFI		348,133	357,059	394,032
Allowance for loan and lease losses		$ (12,876)	$ (13,275)	$ (14,757)	$ (14,833)

[1] Represents net acquisition discounts of $143.0 million and net purchase premiums of $75.4 million at March 31, 2026, and net acquisition discounts of $158.5 million and net purchase premiums of $72.4 million at December 31, 2025

[2] Excludes accrued interest receivable of $106.2 million and $104.3 million at March 31, 2026 and December 31, 2025, respectively, which is recorded in "Other assets" on the consolidated balance sheets.

[3] Includes land and acquisition and development loans of $217.8 million and $214.5 million at March 31, 2026 and December 31, 2025