Loans Receivable and Allowance for Credit Losses - Loan Purchases, Sales and Transfers (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Loans Receivable and Allowance for Credit Losses
Loans transferred from held-for-investment to held-for-sale	$ 218,189	$ 101,764	$ 351,406	$ 247,636
Loans transferred from held-for-sale to held-for-investment	631		631	0
Sales	189,883	104,180	319,588	257,597
Purchases	316,789	231,578	541,760	542,426
Writeoff	158	1,300	217	1,300
Net gains on sales of loans	917	1,491	3,839	3,272
Commercial and industrial (“C&I”) \| Originated
Loans Receivable and Allowance for Credit Losses
Sales	55,400	67,600	167,700	198,600
Loans sold in secondary market \| Purchased
Loans Receivable and Allowance for Credit Losses
Sales	134,500	36,600	151,900	59,000
Commercial lending \| Commercial and industrial (“C&I”)
Loans Receivable and Allowance for Credit Losses
Loans transferred from held-for-investment to held-for-sale	208,335	84,745	319,772	210,585
Loans transferred from held-for-sale to held-for-investment	0		0
Sales	180,029	84,503	287,503	210,382
Purchases	194,066	66,415	304,662	245,093
Commercial lending \| Commercial real estate (“CRE”)
Loans Receivable and Allowance for Credit Losses
Loans transferred from held-for-investment to held-for-sale	9,854	17,019	31,634	37,051
Loans transferred from held-for-sale to held-for-investment	0		0
Sales	9,854	17,019	31,634	37,051
Purchases	0	0	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	0	0	0	0
Loans transferred from held-for-sale to held-for-investment	0		0
Sales	0	0	0	0
Purchases	0	0	0	370
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	2,658	451	10,164
Purchases	$ 122,723	$ 165,163	$ 237,098	$ 296,963

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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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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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