Loans Receivable and Allowance for Credit Losses - Loan Purchases, Sales and Transfers (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Loans Receivable and Allowance for Credit Losses
Loans transferred from held-for-investment to held-for-sale	$ 227,189	$ 112,363	$ 507,215	$ 463,769
Loans transferred from held-for-sale to held-for-investment				631
Sales	228,868	127,165	532,289	446,753
Purchases	160,359	57,662	432,430	599,422
Writeoff	3,600	8,700	4,200	8,900
Originated
Loans Receivable and Allowance for Credit Losses
Sales	204,100	86,200	407,300	253,900
Loans sold in secondary market \| Purchased
Loans Receivable and Allowance for Credit Losses
Sales	24,700	40,900	125,000	192,900
Commercial lending \| Commercial and industrial (“C&I”)
Loans Receivable and Allowance for Credit Losses
Loans transferred from held-for-investment to held-for-sale	201,299	59,069	469,571	378,841
Loans transferred from held-for-sale to held-for-investment				0
Sales	199,511	87,597	491,178	375,100
Purchases	19,588	56,507	80,550	361,169
Commercial lending \| CRE
Loans Receivable and Allowance for Credit Losses
Loans transferred from held-for-investment to held-for-sale	25,890	33,616	29,490	65,250
Loans transferred from held-for-sale to held-for-investment				0
Sales	29,357	33,616	32,957	65,250
Purchases	0	0	0	0
Commercial lending \| Construction and land
Loans Receivable and Allowance for Credit Losses
Loans transferred from held-for-investment to held-for-sale	0		8,154
Sales	0		8,154
Purchases	0		0
Commercial lending \| Real estate loan \| Multifamily residential
Loans Receivable and Allowance for Credit Losses
Loans transferred from held-for-investment to held-for-sale		14,500		14,500
Loans transferred from held-for-sale to held-for-investment				0
Sales		0		0
Purchases		0		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	5,178	0	5,178
Loans transferred from held-for-sale to held-for-investment				631
Sales	0	5,952	0	6,403
Purchases	$ 140,771	$ 1,155	$ 351,880	$ 238,253

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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.

+ References

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-Topic 326
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Amount of increase in financing receivable from purchase. Excludes net investment in lease.

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