Portfolio Loans - Schedule of activity on the allowance for loan losses (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Activity in the allowance for loan losses
ACL beginning balance	$ 91,639	$ 88,757	$ 91,608	$ 87,887
Provision for credit losses	364	2,364	1,944	3,764
Charged-off	(1,115)	(819)	(3,643)	(2,623)
Recoveries	822	420	1,801	1,694
ACL ending balance	91,710	90,722	91,710	90,722
Commercial
Activity in the allowance for loan losses
ACL beginning balance	24,510	23,359	23,860	23,855
Provision for credit losses	(1,306)	615	79	123
Charged-off	(758)	(381)	(1,733)	(589)
Recoveries	187	102	427	306
ACL ending balance	22,633	23,695	22,633	23,695
Commercial real estate
Activity in the allowance for loan losses
ACL beginning balance	33,656	37,182	38,299	38,249
Provision for credit losses	745	598	(3,006)	408
Charged-off	(102)	0	(1,175)	(1,372)
Recoveries	392	19	573	514
ACL ending balance	34,691	37,799	34,691	37,799
Real estate construction
Activity in the allowance for loan losses
ACL beginning balance	5,071	5,669	6,457	5,102
Provision for credit losses	104	216	(1,404)	663
Charged-off	0	0	0	0
Recoveries	31	86	153	206
ACL ending balance	5,206	5,971	5,206	5,971
Retail real estate
Activity in the allowance for loan losses
ACL beginning balance	24,675	17,984	18,193	17,589
Provision for credit losses	674	684	6,975	826
Charged-off	(144)	(220)	(252)	(253)
Recoveries	128	172	417	458
ACL ending balance	25,333	18,620	25,333	18,620
Retail other
Activity in the allowance for loan losses
ACL beginning balance	3,727	4,563	4,799	3,092
Provision for credit losses	147	251	(700)	1,744
Charged-off	(111)	(218)	(483)	(409)
Recoveries	84	41	231	210
ACL ending balance	$ 3,847	$ 4,637	$ 3,847	$ 4,637

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

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- Definition

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

+ References

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

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

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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 6
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-6

Reference 2: 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

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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

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