Bank segment - Credit risk profile - nonaccrual loans (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2020	Dec. 31, 2019
Credit risk profile based on nonaccrual loans
With a Related ACL	$ 35,954
Without a Related ACL	6,026
Total	41,980	$ 29,736
Total troubled debt restructuring loans not included above	22,506	26,413
Real estate \| Residential 1-4 family
Credit risk profile based on nonaccrual loans
With a Related ACL	8,271
Without a Related ACL	1,919
Total	10,190	11,395
Total troubled debt restructuring loans not included above	8,224	9,869
Real estate \| Commercial real estate
Credit risk profile based on nonaccrual loans
With a Related ACL	15,965
Without a Related ACL	0
Total	15,965	195
Total troubled debt restructuring loans not included above	997	853
Real estate \| Home equity line of credit
Credit risk profile based on nonaccrual loans
With a Related ACL	6,246
Without a Related ACL	1,555
Total	7,801	6,638
Total troubled debt restructuring loans not included above	8,809	10,376
Real estate \| Residential land
Credit risk profile based on nonaccrual loans
With a Related ACL	410
Without a Related ACL	0
Total	410	448
Total troubled debt restructuring loans not included above	1,891	2,644
Real estate \| Commercial construction
Credit risk profile based on nonaccrual loans
With a Related ACL	0
Without a Related ACL	0
Total	0	0
Total troubled debt restructuring loans not included above	0	0
Real estate \| Residential construction
Credit risk profile based on nonaccrual loans
With a Related ACL	0
Without a Related ACL	0
Total	0	0
Total troubled debt restructuring loans not included above	0	0
Commercial
Credit risk profile based on nonaccrual loans
With a Related ACL	758
Without a Related ACL	2,552
Total	3,310	5,947
Total troubled debt restructuring loans not included above	2,531	2,614
Consumer
Credit risk profile based on nonaccrual loans
With a Related ACL	4,304
Without a Related ACL	0
Total	4,304	5,113
Total troubled debt restructuring loans not included above	$ 54	$ 57

Financing Receivable, Nonaccrual, With Allowance

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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 http://asc.fasb.org/extlink&oid=121611835&loc=SL6953676-111524

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- Definition

Amount of financing receivable on nonaccrual status with no allowance for credit loss.

+ 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 http://asc.fasb.org/extlink&oid=121599337&loc=SL82919258-210447

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Amount of financing receivable on nonaccrual status.

+ 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 http://asc.fasb.org/extlink&oid=121611835&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 http://asc.fasb.org/extlink&oid=121599337&loc=SL82919258-210447

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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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