Bank segment - Loan modifications (Details) - Troubled debt restructurings real estate loans $ in Thousands	3 Months Ended
Mar. 31, 2021 USD ($) contract
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of contracts \| contract	17
Outstanding recorded investment	$ 9,265
Related allowance	$ 349
Real estate \| Residential 1-4 family
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of contracts \| contract	12
Outstanding recorded investment	$ 8,283
Related allowance	$ 298
Real estate \| Commercial real estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of contracts \| contract	1
Outstanding recorded investment	$ 482
Related allowance	$ 0
Real estate \| Home equity line of credit
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of contracts \| contract	1
Outstanding recorded investment	$ 170
Related allowance	$ 21
Real estate \| Residential land
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of contracts \| contract	1
Outstanding recorded investment	$ 271
Related allowance	$ 11
Real estate \| Commercial construction
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of contracts \| contract	0
Outstanding recorded investment	$ 0
Related allowance	$ 0
Real estate \| Residential construction
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of contracts \| contract	0
Outstanding recorded investment	$ 0
Related allowance	$ 0
Commercial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of contracts \| contract	2
Outstanding recorded investment	$ 59
Related allowance	$ 19
Consumer
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of contracts \| contract	0
Outstanding recorded investment	$ 0
Related allowance	$ 0

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

No definition available.

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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.

+ Details

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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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- Definition

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

+ References

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