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Loans and Allowance for Credit Losses on Loans - TDR (Details)	3 Months Ended	12 Months Ended
	Dec. 31, 2020 USD ($) contract	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($) contract
Troubled debt restructurings - modified during the period
# of contracts	1,000		3
Pre-modification recorded investment	$ 154,000		$ 410,000
Post-modification recorded investment	153,000		395,000
Other information
Commitments to lend to borrowers whose loans were classified as impaired	$ 0	$ 0	$ 0
Financing receivable, purchase		0
Financing receivable, sales		0
Residential owner-occupied | Home Affordable Modification Program [Member]
Troubled debt restructurings - modified during the period
# of contracts | contract	1		3
Pre-modification recorded investment	$ 154,000		$ 410,000
Post-modification recorded investment	$ 153,000		395,000
HELOC | Others [Member]
TDR's defaulted
Pre-modification outstanding recorded investment during the period		$ 0	$ 0

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