Loans Receivable and Allowance for Credit Losses - Loan Purchases, Sales and Transfers (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Loans Receivable and Allowance for Credit Losses
Loans transferred from held-for-investment to held-for-sale	$ 119,550	$ 218,189	$ 280,026	$ 351,406
Loans transferred from held-for-sale to held-for-investment		631	0	631
Sales	123,889	189,883	303,421	319,588
Purchases	117,416	316,789	272,098	541,760
Writeoff	308	158	581	217
Net (losses) gains on sales of loans	(7)	917	(29)	3,839
Originated
Loans Receivable and Allowance for Credit Losses
Sales	92,200	55,400	203,200	167,700
Loans sold in secondary market \| Purchased
Loans Receivable and Allowance for Credit Losses
Sales	31,700	134,500	100,300	151,900
Commercial lending \| Commercial and industrial (“C&I”)
Loans Receivable and Allowance for Credit Losses
Loans transferred from held-for-investment to held-for-sale	111,396	208,335	268,272	319,772
Loans transferred from held-for-sale to held-for-investment		0		0
Sales	115,735	180,029	291,667	287,503
Purchases	38,279	194,066	60,962	304,662
Commercial lending \| CRE
Loans Receivable and Allowance for Credit Losses
Loans transferred from held-for-investment to held-for-sale	0	9,854	3,600	31,634
Loans transferred from held-for-sale to held-for-investment		0		0
Sales	0	9,854	3,600	31,634
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	8,154		8,154
Sales	8,154		8,154
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	0	0	0
Loans transferred from held-for-sale to held-for-investment		631		631
Sales	0	0	0	451
Purchases	$ 79,137	$ 122,723	$ 211,136	$ 237,098

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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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Amount of decrease in financing receivable from sale and reclassification to held-for-sale. Excludes net investment in lease.

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The net gain (loss) resulting from a sale of loans, including adjustments to record loans classified as held-for-sale at the lower-of-cost-or-market and fair value adjustments to loan held for investment purposes.

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

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