Loans and Allowance for Credit Losses - CECL allowance (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2026	Mar. 31, 2025
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	$ 15,862	$ 23,662
Provision for (recovery of) credit losses related to loans	5,372	1,052
Charge-offs	(5,532)	(791)
Ending balance	15,702	23,923
Loans held for investment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	11,510	18,470
Provision for (recovery of) credit losses related to loans	4,771	273
Charge-offs	(3,880)	(621)
Ending balance	12,401	18,122
Interest and fees receivable
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	2,598	3,133
Provision for (recovery of) credit losses related to loans	(24)	(152)
Charge-offs	(1,652)	0
Ending balance	922	2,981
Due from borrower
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	1,084	1,135
Provision for (recovery of) credit losses related to loans	707	991
Charge-offs	0	(170)
Ending balance	1,791	1,956
Unfunded commitments
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	670	924
Provision for (recovery of) credit losses related to loans	(82)	(60)
Charge-offs	0	0
Ending balance	$ 588	$ 864

Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479344/326-20-45-1

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

Amount, excluding accrued interest, of decrease in allowance for credit loss on financing receivable from writeoff. 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 13
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-6

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- Definition

Amount, excluding accrued interest, of credit loss expense (reversal of expense) on financing receivable. 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 13
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 220
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 22
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147476148/220-40-50-22

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