Loans Receivable and Allowance for Credit Losses (Loan Purchases, Sales and Transfers) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Loans Receivable and Allowance for Credit Losses
Sales	$ 129,705	$ 153,417
Purchases	224,971	310,848
Allowance for loan and lease losses, Loans transferred from held-for-investment to held-for-sale, write-offs	59	39
Net gains on sales of loans	2,922	1,781
Loans transferred from held-for-investment to held-for-sale	133,217	145,872
Commercial and industrial (“C&I”) \| Originated
Loans Receivable and Allowance for Credit Losses
Sales	112,300	131,000
Loans sold in secondary market \| Purchased
Loans Receivable and Allowance for Credit Losses
Sales	17,400	22,400
Commercial lending \| Commercial and industrial (“C&I”)
Loans Receivable and Allowance for Credit Losses
Sales	107,474	125,879
Purchases	110,596	178,678
Loans transferred from held-for-investment to held-for-sale	111,437	125,840
Commercial lending \| Commercial real estate (“CRE”)
Loans Receivable and Allowance for Credit Losses
Sales	21,780	20,032
Purchases	0	0
Loans transferred from held-for-investment to held-for-sale	21,780	20,032
Commercial lending \| Real estate loan \| Multifamily residential
Loans Receivable and Allowance for Credit Losses
Sales	0	0
Purchases	0	370
Loans transferred from held-for-investment to held-for-sale	0	0
Consumer lending \| Real estate loan \| Single-family residential
Loans Receivable and Allowance for Credit Losses
Sales	451	7,506
Purchases	114,375	131,800
Loans transferred from held-for-investment to held-for-sale	$ 0	$ 0

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Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

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Amount of increase from purchase of financing receivable.

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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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