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Loans and Allowance for Credit Losses on Loans - Collateral dependent loans (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans pledged as collateral	$ 29,733	$ 29,253
ACL Allocation	26,949	33,855
Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans pledged as collateral	23,249	25,150
Accounts Receivable
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans pledged as collateral		1,070
Equipment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans pledged as collateral	3,413	2,377
Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans pledged as collateral	3,071	656
Collateral
Accounts, Notes, Loans and Financing Receivable [Line Items]
ACL Allocation	4,233	2,637
Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans pledged as collateral	195	1,125
Commercial | Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans pledged as collateral	195
Commercial | Accounts Receivable
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans pledged as collateral		1,070
Commercial | Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans pledged as collateral		55
Commercial | Collateral
Accounts, Notes, Loans and Financing Receivable [Line Items]
ACL Allocation		56
Leases
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans pledged as collateral	3,959	2,974
Leases | Equipment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans pledged as collateral	3,413	2,377
Leases | Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans pledged as collateral	546	597
Leases | Collateral
Accounts, Notes, Loans and Financing Receivable [Line Items]
ACL Allocation	661	880
Commercial real estate - Investor
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans pledged as collateral	6,070	4,179
Commercial real estate - Investor | Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans pledged as collateral	6,070	4,179
Commercial real estate - Investor | Collateral
Accounts, Notes, Loans and Financing Receivable [Line Items]
ACL Allocation	2,290	84
Commercial real estate - Owner occupied
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans pledged as collateral	6,896	9,726
Commercial real estate - Owner occupied | Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans pledged as collateral	4,373	9,726
Commercial real estate - Owner occupied | Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans pledged as collateral	2,523
Commercial real estate - Owner occupied | Collateral
Accounts, Notes, Loans and Financing Receivable [Line Items]
ACL Allocation	7	195
Construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans pledged as collateral	4,898	1,891
Construction | Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans pledged as collateral	4,898	1,891
Construction | Collateral
Accounts, Notes, Loans and Financing Receivable [Line Items]
ACL Allocation	988	952
Residential real estate - Investor
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans pledged as collateral	998	928
Residential real estate - Investor | Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans pledged as collateral	998	928
Residential real estate - Owner occupied
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans pledged as collateral	3,945	3,535
Residential real estate - Owner occupied | Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans pledged as collateral	3,945	3,535
Residential real estate - Owner occupied | Collateral
Accounts, Notes, Loans and Financing Receivable [Line Items]
ACL Allocation		10
Multifamily
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans pledged as collateral	1,889	3,838
Multifamily | Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans pledged as collateral	1,889	3,838
Multifamily | Collateral
Accounts, Notes, Loans and Financing Receivable [Line Items]
ACL Allocation	90	378
HELOC
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans pledged as collateral	700	1,053
HELOC | Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans pledged as collateral	700	1,053
HELOC | Collateral
Accounts, Notes, Loans and Financing Receivable [Line Items]
ACL Allocation	195	78
HELOC - Purchased
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans pledged as collateral	181
HELOC - Purchased | Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans pledged as collateral	181
Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans pledged as collateral	2	4
Other | Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans pledged as collateral	2	4
Other | Collateral
Accounts, Notes, Loans and Financing Receivable [Line Items]
ACL Allocation	$ 2	$ 4

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Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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Carrying amount as of the balance sheet date of loans that have been pledged as collateral for borrowings. If the secured party has the right by contract or custom to sell or re-pledge the collateral, then the debtor reclassifies that asset and report that asset in its statement of financial position separately from other assets not so encumbered.

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