Loans and Leases Held for Investment - Allowance for Loan and Lease Losses (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2026	Mar. 31, 2025	Dec. 31, 2025	Dec. 31, 2024
Allowance for Loan and Lease Losses [Roll Forward]
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest	$ 241,600	$ 234,986	$ 245,612	$ 239,360
Allowance for Credit Losses, Charge-offs	16,097	16,551
Allowance for Credit Losses, Recoveries	2,285	2,477
Financing Receivable, Allowance for Credit Loss, Writeoff, after Recovery	13,812	14,074
Financing Receivable, Excluding Accrued Interest, Credit Loss Expense (Reversal)	9,800	9,700
Amount of the allowance applicable to loans and leases:
Individually evaluated	2,200	3,327
Collectively evaluated	239,400	231,659
The ending balance of the loan and lease portfolio is composed of loans and leases:
Individually evaluated	183,243	210,210
Collectively evaluated	24,597,104	23,916,317
Loans and leases HFI	24,780,347	24,126,527	25,032,679
Real Estate Mortgage
Allowance for Loan and Lease Losses [Roll Forward]
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest	131,514	130,116	137,401	145,754
Allowance for Credit Losses, Charge-offs	5,374	5,789
Allowance for Credit Losses, Recoveries	802	311
Financing Receivable, Allowance for Credit Loss, Writeoff, after Recovery	4,572	5,478
Financing Receivable, Excluding Accrued Interest, Credit Loss Expense (Reversal)	1,315	(10,160)
Amount of the allowance applicable to loans and leases:
Individually evaluated	0	1,702
Collectively evaluated	131,514	128,414
The ending balance of the loan and lease portfolio is composed of loans and leases:
Individually evaluated	153,985	198,839
Collectively evaluated	13,352,913	13,293,819
Loans and leases HFI	13,506,898	13,492,658	13,750,787
Real Estate Construction and Land
Allowance for Loan and Lease Losses [Roll Forward]
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest	10,395	14,124	8,849	10,940
Allowance for Credit Losses, Charge-offs	8,077	0
Allowance for Credit Losses, Recoveries	0	0
Financing Receivable, Allowance for Credit Loss, Writeoff, after Recovery	8,077	0
Financing Receivable, Excluding Accrued Interest, Credit Loss Expense (Reversal)	9,623	3,184
Amount of the allowance applicable to loans and leases:
Individually evaluated	0	0
Collectively evaluated	10,395	14,124
The ending balance of the loan and lease portfolio is composed of loans and leases:
Individually evaluated	0	0
Collectively evaluated	1,892,329	2,861,038
Loans and leases HFI	1,892,329	2,861,038	1,947,627
Commercial
Allowance for Loan and Lease Losses [Roll Forward]
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest	86,815	75,989	86,087	67,833
Allowance for Credit Losses, Charge-offs	1,737	9,582
Allowance for Credit Losses, Recoveries	1,307	2,104
Financing Receivable, Allowance for Credit Loss, Writeoff, after Recovery	430	7,478
Financing Receivable, Excluding Accrued Interest, Credit Loss Expense (Reversal)	1,158	15,634
Amount of the allowance applicable to loans and leases:
Individually evaluated	2,200	1,625
Collectively evaluated	84,615	74,364
The ending balance of the loan and lease portfolio is composed of loans and leases:
Individually evaluated	29,258	11,371
Collectively evaluated	9,003,729	7,367,428
Loans and leases HFI	9,032,987	7,378,799	8,977,206
Consumer
Allowance for Loan and Lease Losses [Roll Forward]
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest	12,876	14,757	13,275	$ 14,833
Allowance for Credit Losses, Charge-offs	909	1,180
Allowance for Credit Losses, Recoveries	176	62
Financing Receivable, Allowance for Credit Loss, Writeoff, after Recovery	733	1,118
Financing Receivable, Excluding Accrued Interest, Credit Loss Expense (Reversal)	334	1,042
Amount of the allowance applicable to loans and leases:
Individually evaluated	0	0
Collectively evaluated	12,876	14,757
The ending balance of the loan and lease portfolio is composed of loans and leases:
Individually evaluated	0	0
Collectively evaluated	348,133	394,032
Loans and leases HFI	$ 348,133	$ 394,032	$ 357,059

Financing Receivable, Allowance for Credit Loss, Additional Information, Portfolio Composition [Abstract]

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease.

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Amount, after recovery, of writeoff of financing receivable, charged against allowance for credit loss.

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Amount of allowance for credit loss on financing receivable evaluated on collective basis. Excludes financing receivable evaluated on individual basis.

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Amount of allowance for credit loss on financing receivable evaluated on individual basis. Excludes financing receivable evaluated on collective basis.

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Amount of increase in allowance for credit loss on financing receivable from recovery.

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Amount, excluding accrued interest, of credit loss expense (reversal of expense) on financing receivable. Excludes net investment in lease.

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