Bank segment - Collateral - Dependent loans (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Financing Receivable, Nonaccrual [Line Items]
Consumer mortgage loans collateralized by residential real estate property in foreclosure process	$ 3,300	$ 4,200
Residential real estate property | Real estate | Residential 1-4 family
Financing Receivable, Nonaccrual [Line Items]
Collateral-dependent loans, amortized cost	2,712	3,959
Residential real estate property | Real estate | Home equity line of credit
Financing Receivable, Nonaccrual [Line Items]
Collateral-dependent loans, amortized cost	740	1,425
Collateral pledged
Financing Receivable, Nonaccrual [Line Items]
Collateral-dependent loans, amortized cost	3,832	5,384
Collateral pledged | Real estate
Financing Receivable, Nonaccrual [Line Items]
Collateral-dependent loans, amortized cost	3,452	5,384
Business assets | Commercial
Financing Receivable, Nonaccrual [Line Items]
Collateral-dependent loans, amortized cost	$ 380	$ 0