Loans Receivable and Allowance for Credit Losses - Loan Purchases, Sales and Transfers (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2023	Mar. 31, 2022
Loans Receivable and Allowance for Credit Losses
Loans transferred from held-for-investment to held-for-sale	$ 160,476	$ 133,217
Sales	179,532	129,705
Purchases	154,682	224,971
Writeoff	273	59
Net (losses) gains on sales of loans	(22)	2,922
C&I and CRE \| Originated
Loans Receivable and Allowance for Credit Losses
Sales	111,000	112,300
Loans sold in secondary market \| Purchased
Loans Receivable and Allowance for Credit Losses
Sales	68,500	17,400
Commercial lending \| Commercial and industrial (“C&I”)
Loans Receivable and Allowance for Credit Losses
Loans transferred from held-for-investment to held-for-sale	156,876	111,437
Sales	175,932	107,474
Purchases	22,683	110,596
Commercial lending \| CRE
Loans Receivable and Allowance for Credit Losses
Loans transferred from held-for-investment to held-for-sale	3,600	21,780
Sales	3,600	21,780
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
Sales	0	451
Purchases	$ 131,999	$ 114,375

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

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