Investment Securities - Securities in Continuous Unrealized Loss Position (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Schedule Of Investments [Line Items]
Available-for-sale, less than 12 months, fair value	$ 10,792	$ 15,041
Available-for-sale, less than 12 months, unrealized losses	(22)	(3)
Available-for-sale, 12 months or more, fair value	3,969	4,346
Available-for-sale, 12 months or more, unrealized losses	(65)	(148)
Held-to-maturity, less than 12 months, fair value	48	412
Residential Mortgage Backed Securities [Member]
Schedule Of Investments [Line Items]
Available-for-sale, less than 12 months, fair value	183	2,334
Available-for-sale, less than 12 months, unrealized losses		(1)
Available-for-sale, 12 months or more, fair value	781	1,019
Available-for-sale, 12 months or more, unrealized losses	(4)	(7)
Commercial Mortgage Backed Securities [Member]
Schedule Of Investments [Line Items]
Available-for-sale, less than 12 months, fair value	453	2,630
Available-for-sale, less than 12 months, unrealized losses		(1)
Available-for-sale, 12 months or more, fair value	3,188	3,327
Available-for-sale, 12 months or more, unrealized losses	(61)	(141)
Held-to-maturity, less than 12 months, fair value	48	412
US Treasury Securities [Member]
Schedule Of Investments [Line Items]
Available-for-sale, less than 12 months, fair value	10,156	10,077
Available-for-sale, less than 12 months, unrealized losses	$ (22)	$ (1)

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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Amount of accumulated unrealized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for 12 months or longer, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for less than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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