Loans Receivable and Allowance for Credit Losses - Loan Purchases, Sales and Transfers (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2024	Mar. 31, 2023
Loans Receivable and Allowance for Credit Losses
Loans transferred from held-for-investment to held-for-sale	$ 199,974	$ 160,476
Sales	188,167	179,532
Purchases	108,080	154,682
Writeoff	1,000	273
Originated
Loans Receivable and Allowance for Credit Losses
Sales	92,000	111,000
Loans sold in secondary market \| Purchased
Loans Receivable and Allowance for Credit Losses
Sales	96,000	69,000
Commercial lending \| Commercial and industrial (“C&I”)
Loans Receivable and Allowance for Credit Losses
Loans transferred from held-for-investment to held-for-sale	199,974	156,876
Sales	187,202	175,932
Purchases	33,344	22,683
Commercial lending \| CRE
Loans Receivable and Allowance for Credit Losses
Loans transferred from held-for-investment to held-for-sale		3,600
Sales		3,600
Purchases		0
Consumer lending \| Real estate loan \| Single-family residential
Loans Receivable and Allowance for Credit Losses
Loans transferred from held-for-investment to held-for-sale	0	0
Sales	965	0
Purchases	$ 74,736	$ 131,999

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

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Amount of increase in financing receivable from purchase. Excludes net investment in lease.

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Value of loans and leases held in the entity's portfolio transferred to loans and leases held-for-sale in noncash transactions.

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