Bank segment - Allowance for Credit Losses (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2024	Mar. 31, 2023
Allowance for credit losses:
Beginning balance	$ 74,372	$ 72,216
Charge-offs	(3,675)	(3,422)
Recoveries	1,519	1,327
Provision	(1,159)	1,175
Ending balance	71,057	71,296
Residential 1-4 family
Allowance for credit losses:
Charge-offs	(842)	(809)
Commercial real estate
Allowance for credit losses:
Charge-offs	0	0
Home equity line of credit
Allowance for credit losses:
Charge-offs	0	(63)
Residential land
Allowance for credit losses:
Charge-offs	0	0
Commercial construction
Allowance for credit losses:
Charge-offs	0	0
Residential construction
Allowance for credit losses:
Charge-offs	0	0
Real estate \| Residential 1-4 family
Allowance for credit losses:
Beginning balance	7,435	6,270
Charge-offs	(842)	(809)
Recoveries	186	4
Provision	(373)	(853)
Ending balance	6,406	4,612
Real estate \| Commercial real estate
Allowance for credit losses:
Beginning balance	22,185	21,898
Charge-offs	0	0
Recoveries	0	0
Provision	(1,851)	803
Ending balance	20,334	22,701
Real estate \| Home equity line of credit
Allowance for credit losses:
Beginning balance	7,778	6,125
Charge-offs	0	(63)
Recoveries	238	17
Provision	57	(26)
Ending balance	8,073	6,053
Real estate \| Residential land
Allowance for credit losses:
Beginning balance	621	717
Charge-offs	0	0
Recoveries	0	0
Provision	51	(97)
Ending balance	672	620
Real estate \| Commercial construction
Allowance for credit losses:
Beginning balance	3,603	1,195
Charge-offs	0	0
Recoveries	0	0
Provision	(202)	(460)
Ending balance	3,401	735
Real estate \| Residential construction
Allowance for credit losses:
Beginning balance	43	46
Charge-offs	0	0
Recoveries	0	0
Provision	(2)	(18)
Ending balance	41	28
Commercial
Allowance for credit losses:
Beginning balance	9,122	12,426
Charge-offs	(114)	(227)
Recoveries	95	398
Provision	(1,489)	(661)
Ending balance	7,614	11,936
Consumer
Allowance for credit losses:
Beginning balance	23,585	23,539
Charge-offs	(2,719)	(2,323)
Recoveries	1,000	908
Provision	2,650	2,487
Ending balance	$ 24,516	$ 24,611

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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+ References

No definition available.

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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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