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Loans and Allowance for Credit Losses on Loans - TDR (Details)	12 Months Ended
	Dec. 31, 2020 USD ($) contract	Dec. 31, 2019 USD ($) contract
Troubled debt restructurings - modified during the period
# of contracts | contract	3	7
Pre-modification balance	$ 410,000	$ 2,076,000
Post-modification balance	395,000	1,949,000
Other information
Commitments to lend to borrowers whose loans were classified as impaired	0	$ 0
Financing receivable, purchase	0
Financing receivable, sales	$ 0
Residential Owner Occupied Loan [Member] | Home Affordable Modification Program [Member]
Troubled debt restructurings - modified during the period
# of contracts | contract	3	3
Pre-modification balance	$ 410,000	$ 399,000
Post-modification balance	395,000	$ 293,000
Commercial real estate - Investor | Others [Member]
Troubled debt restructurings - modified during the period
# of contracts | contract		2
Pre-modification balance		$ 1,217,000
Post-modification balance		$ 1,200,000
Commercial real estate - Owner occupied | Deferral [Member]
Troubled debt restructurings - modified during the period
# of contracts | contract		1
Pre-modification balance		$ 421,000
Post-modification balance		$ 418,000
HELOC | Others [Member]
Troubled debt restructurings - modified during the period
# of contracts | contract		1
Pre-modification balance		$ 39,000
Post-modification balance		38,000
TDR's defaulted
Pre-modification outstanding recorded investment during the period	$ 0	$ 39,000

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