Bank segment - Credit risk profile - nonaccrual loans (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2022	Mar. 31, 2023
Credit risk profile based on nonaccrual loans
With a Related ACL	$ 12,043	$ 11,133
Without a Related ACL	4,423	3,354
Total	16,466	14,487
Total troubled debt restructuring loans not included above	30,130
Real estate \| Residential 1-4 family
Credit risk profile based on nonaccrual loans
With a Related ACL	4,198	3,371
Without a Related ACL	2,981	2,117
Total	7,179	5,488
Total troubled debt restructuring loans not included above	8,821
Real estate \| Commercial real estate
Credit risk profile based on nonaccrual loans
With a Related ACL	0	0
Without a Related ACL	0	0
Total	0	0
Total troubled debt restructuring loans not included above	9,477
Real estate \| Home equity line of credit
Credit risk profile based on nonaccrual loans
With a Related ACL	3,654	4,014
Without a Related ACL	1,442	1,237
Total	5,096	5,251
Total troubled debt restructuring loans not included above	4,404
Real estate \| Residential land
Credit risk profile based on nonaccrual loans
With a Related ACL	420	109
Without a Related ACL	0	0
Total	420	109
Total troubled debt restructuring loans not included above	782
Real estate \| Commercial construction
Credit risk profile based on nonaccrual loans
With a Related ACL	0	0
Without a Related ACL	0	0
Total	0	0
Total troubled debt restructuring loans not included above	0
Real estate \| Residential construction
Credit risk profile based on nonaccrual loans
With a Related ACL	0	0
Without a Related ACL	0	0
Total	0	0
Total troubled debt restructuring loans not included above	0
Commercial
Credit risk profile based on nonaccrual loans
With a Related ACL	2,183	1,744
Without a Related ACL	0	0
Total	2,183	1,744
Total troubled debt restructuring loans not included above	6,596
Consumer
Credit risk profile based on nonaccrual loans
With a Related ACL	1,588	1,895
Without a Related ACL	0	0
Total	1,588	$ 1,895
Total troubled debt restructuring loans not included above	$ 50

Financing Receivable, Nonaccrual, With Allowance

No definition available.

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- Definition

Amount, after troubled debt restructuring, of modified financing receivable.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI https://asc.fasb.org/extlink&oid=123577603&loc=SL6953676-111524

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- Definition

Amortized cost of financing receivable on nonaccrual status with no allowance for credit loss. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 16
-Subparagraph (d)
-URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919258-210447

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- Definition

Amortized cost of financing receivable on nonaccrual status. Excludes net investment in lease.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=123577603&loc=d3e5111-111524

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 16
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919258-210447

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher SEC
-Name Regulation S-K (SK)
-Number 229
-Section 1405
-Paragraph (a)
-Subparagraph (3)

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher SEC
-Name Regulation S-K (SK)
-Number 229
-Section 1405
-Paragraph (a)
-Subparagraph (2)

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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