Allowance for Credit Losses - Loan Portfolio (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Allowance for credit losses activity by loan portfolio
Beginning balance	$ 39,651	$ 40,518	$ 40,518
Provision charged to operations	3,600	1,950
Loans charged off	(4,204)	(3,213)	(3,213)
Recoveries of loans previously charged off	1,153	1,088
Ending balance	40,200	40,834	39,651
Impact of ASC 326 \| Accounting Standards Update 2016-13 \| Non-PCD loans
Allowance for credit losses activity by loan portfolio
Ending balance		(113)
Impact of ASC 326 \| Accounting Standards Update 2016-13 \| PCD loans
Allowance for credit losses activity by loan portfolio
Ending balance		604
Commercial
Allowance for credit losses activity by loan portfolio
Beginning balance	12,315	11,219	11,219
Provision charged to operations	535	233
Loans charged off		(16)
Recoveries of loans previously charged off	9	35
Ending balance	12,859	11,449	12,315
Commercial \| Impact of ASC 326 \| Accounting Standards Update 2016-13 \| Non-PCD loans
Allowance for credit losses activity by loan portfolio
Ending balance		(617)
Commercial \| Impact of ASC 326 \| Accounting Standards Update 2016-13 \| PCD loans
Allowance for credit losses activity by loan portfolio
Ending balance		595
Consumer
Allowance for credit losses activity by loan portfolio
Beginning balance	3,758	3,330	3,330
Provision charged to operations	65	117
Loans charged off	(101)	(89)
Recoveries of loans previously charged off	53	45
Ending balance	3,775	3,510	3,758
Consumer \| Impact of ASC 326 \| Accounting Standards Update 2016-13 \| Non-PCD loans
Allowance for credit losses activity by loan portfolio
Ending balance		98
Consumer \| Impact of ASC 326 \| Accounting Standards Update 2016-13 \| PCD loans
Allowance for credit losses activity by loan portfolio
Ending balance		9
Consumer finance
Allowance for credit losses activity by loan portfolio
Beginning balance	23,578	25,969	25,969
Provision charged to operations	3,000	1,600
Loans charged off	(4,103)	(3,108)
Recoveries of loans previously charged off	1,091	1,008
Ending balance	$ 23,566	25,875	$ 23,578
Consumer finance \| Impact of ASC 326 \| Accounting Standards Update 2016-13 \| Non-PCD loans
Allowance for credit losses activity by loan portfolio
Ending balance		$ 406

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

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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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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