Bank segment - Loan modifications (Details) - Troubled debt restructurings real estate loans $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2021 USD ($) contract	Jun. 30, 2020 USD ($) contract	Jun. 30, 2021 USD ($) contract	Jun. 30, 2020 USD ($) contract
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of contracts \| contract	8	4	24	11
Outstanding recorded investment	$ 2,360	$ 349	$ 11,041	$ 17,677
Related allowance	$ 100	$ 3	$ 338	$ 4,586
Real estate \| Residential 1-4 family
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of contracts \| contract	3	0	15	1
Outstanding recorded investment	$ 1,835	$ 0	$ 10,024	$ 147
Related allowance	$ 77	$ 0	$ 271	$ 7
Real estate \| Commercial real estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of contracts \| contract	0	0	0	2
Outstanding recorded investment	$ 0	$ 0	$ 0	$ 16,430
Related allowance	$ 0	$ 0	$ 0	$ 4,301
Real estate \| Home equity line of credit
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of contracts \| contract	0	2	1	2
Outstanding recorded investment	$ 0	$ 19	$ 163	$ 19
Related allowance	$ 0	$ 3	$ 18	$ 3
Real estate \| Residential land
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of contracts \| contract	1	2	2	2
Outstanding recorded investment	$ 288	$ 330	$ 558	$ 330
Related allowance	$ 12	$ 0	$ 23	$ 0
Real estate \| Commercial construction
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of contracts \| contract	0	0	0	0
Outstanding recorded investment	$ 0	$ 0	$ 0	$ 0
Related allowance	$ 0	$ 0	$ 0	$ 0
Real estate \| Residential construction
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of contracts \| contract	0	0	0	0
Outstanding recorded investment	$ 0	$ 0	$ 0	$ 0
Related allowance	$ 0	$ 0	$ 0	$ 0
Commercial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of contracts \| contract	4	0	6	4
Outstanding recorded investment	$ 237	$ 0	$ 296	$ 751
Related allowance	$ 11	$ 0	$ 26	$ 275
Consumer
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of contracts \| contract	0	0	0	0
Outstanding recorded investment	$ 0	$ 0	$ 0	$ 0
Related allowance	$ 0	$ 0	$ 0	$ 0

Amount of increase (decrease) of allowance reserve for credit loss.

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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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- Definition

Number of financing receivables that have been modified by troubled debt restructurings.

+ 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=123577603&loc=SL6953676-111524

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Amount, before troubled debt restructuring, of financing receivable to be modified.

+ References

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