Loans Receivable and Allowance for Credit Losses - Schedule Of Carrying Value Of Loans Transferred, Loans Sold and Purchased For the Held-For-Investment Portfolio (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Loans Receivable and Allowance for Credit Losses
Loans transferred from held-for-investment to held-for-sale	$ 307,182	$ 227,189	$ 646,797	$ 507,215
Sales	328,406	228,868	651,198	532,289
Purchases	350,546	160,359	740,665	432,430
Write-offs of allowance for loan losses related to loans transferred to held-for-sale	1,000	4,000	2,000	4,000
Originated
Loans Receivable and Allowance for Credit Losses
Sales	309,000	204,000	496,000	407,000
Loans sold in secondary market \| Purchased
Loans Receivable and Allowance for Credit Losses
Sales	20,000	25,000	156,000	125,000
Commercial lending \| C&I
Loans Receivable and Allowance for Credit Losses
Loans transferred from held-for-investment to held-for-sale	307,182	201,299	646,079	469,571
Sales	326,764	199,511	647,873	491,178
Purchases	247,880	19,588	451,399	80,550
Commercial lending \| CRE
Loans Receivable and Allowance for Credit Losses
Loans transferred from held-for-investment to held-for-sale	0	25,890	0	29,490
Sales	0	29,357	0	32,957
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	0	718	8,154
Sales	0	0	718	8,154
Purchases	0	0	0	0
Consumer lending \| Single-family residential
Loans Receivable and Allowance for Credit Losses
Loans transferred from held-for-investment to held-for-sale	0	0	0	0
Sales	1,642	0	2,607	0
Purchases	$ 102,666	$ 140,771	$ 289,266	$ 351,880

Financing Receivable, Excluding Accrued Interest, Allowance For Credit Loss, Writeoff, Reclassification To Held-For-Sale

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- References

No definition available.

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- Definition

Amount excluding accrued interest, of increase in financing receivable from purchase. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 11
-Subparagraph (h)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-11

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- Definition

Amount excluding accrued interest, of financing receivable reclassified to held-for-sale. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 11
-Subparagraph (i)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-11

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- Definition

Amount excluding accrued interest, of decrease in financing receivable from sale. Excludes net investment in lease.

+ References

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