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Investment Securities - Narrative (Details)	3 Months Ended		9 Months Ended
	Sep. 30, 2021 USD ($) security	Sep. 30, 2020 USD ($)	Sep. 30, 2021 USD ($) security segment	Sep. 30, 2020 USD ($)	Dec. 31, 2020 USD ($)
Debt Securities, Available-for-sale [Line Items]
Available-for-sale securities, gross realized gains (losses)	$ 0	$ 0	$ 0	$ 0
OTTI losses, investments	0	0	$ 0	0
Number of general segments for the segregation of portfolio | segment			2
Unrealized (loss) gain on fair value of marketable equity securities	(14,000)	$ 4,000	$ (75,000)	$ 89,000
Held-to-maturity securities	0		0		$ 0
Investment securities	$ 0		$ 0		0
Municipal bonds
Debt Securities, Available-for-sale [Line Items]
Number of impaired securities | security	28		28
U.S. Government agencies
Debt Securities, Available-for-sale [Line Items]
Number of impaired securities | security	6		6
U.S. Government sponsored entities & agencies collateralized by mortgage obligations
Debt Securities, Available-for-sale [Line Items]
Number of impaired securities | security	7		7
Carrying Amount
Debt Securities, Available-for-sale [Line Items]
Fair value of available-for-sale securities pledged as collateral for FHLB borrowings	$ 98,069,000		$ 98,069,000
Investment securities	165,508,000		165,508,000		86,192,000
Estimated Fair Value
Debt Securities, Available-for-sale [Line Items]
Fair value of available-for-sale securities pledged as collateral for FHLB borrowings	98,744,000		98,744,000
Investment securities	$ 165,508,000		$ 165,508,000		$ 86,192,000

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