Loans - Troubled Debt Restructurings (Details) $ in Thousands	12 Months Ended
Dec. 31, 2020 USD ($) loan	Dec. 31, 2019 USD ($) loan
Troubled Debt Restructurings
Loans classified as troubled debt restructurings	$ 28,347	$ 13,718
Allowance for outstanding loan losses classified as troubled debt restructurings	1,951	48
Accrued interest receivable under the CARES Act COVID-19 forbearance program	$ 146
Loans that remain in payment deferral under the CARES Act COVID-19 forbearance program	15,785
Loans amount modified under the CARES Act COVID-19 forbearance program	$ 132,830
Private banking
Troubled Debt Restructurings
Number of loans modified during the period, that were considered as TDRs \| loan	1
Real estate loan, first mortgage
Troubled Debt Restructurings
Loans classified as troubled debt restructurings	$ 209	215
Allowance for outstanding loan losses classified as troubled debt restructurings	41	43
Real estate loan, Retail
Troubled Debt Restructurings
Loans classified as troubled debt restructurings	1,029	1,110
Residential real estate
Troubled Debt Restructurings
Loans secured by residential real estate properties in the process of foreclosure	5,320	1,643
Construction
Troubled Debt Restructurings
Loans classified as troubled debt restructurings	26,985	$ 12,261
Allowance for outstanding loan losses classified as troubled debt restructurings	1,906
Value of loans subsequently defaulted	$ 19,987
Number of loans modified during the period, that were considered as TDRs \| loan	3	3
Financing Receivable, Troubled Debt Restructuring, Subsequent Default	$ 19,987
Number of TDRs subsequently defaulted \| loan	5
Construction \| Pre and Post Modification
Troubled Debt Restructurings
Loans classified as troubled debt restructurings		$ 11,214
Construction loans and private banking loan \| Pre and Post Modification
Troubled Debt Restructurings
Loans classified as troubled debt restructurings	$ 13,777
Commercial lines of credit and private banking
Troubled Debt Restructurings
Loans classified as troubled debt restructurings	124	132
Allowance for outstanding loan losses classified as troubled debt restructurings	$ 4	$ 5

A valuation allowance for modified financing receivables that are expected to be uncollectible.

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Amount of loans modified under the CARES Act COVID-19 forbearance program.

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Amount of interest receivable on loans that remain in payment deferral under the CARES Act COVID-19 forbearance program.

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Number of loans for which the company has received forbearance requests under the CARES Act COVID-19 forbearance program that are still in payment deferral.

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Amount of financing receivable modified as troubled debt restructuring.

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Number of financing receivable contracts modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

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Recorded investment of consumer mortgage loan receivables secured by residential real estate properties for which formal foreclosure proceedings are in process.

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