Investment Securities - Securities in Continuous Unrealized Loss Position (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Schedule Of Investments [Line Items]
Available-for-sale, less than 12 months, fair value	$ 15,041	$ 21,214
Available-for-sale, less than 12 months, unrealized losses	(3)	(91)
Available-for-sale, 12 months or more, fair value	4,346	39,848
Available-for-sale, 12 months or more, unrealized losses	(148)	(504)
Held-to-maturity, less than 12 months, fair value	412	1,531
Held-to-maturity, less than 12 months, unrealized losses		(4)
Held-to-maturity, 12 months or more, fair value		9,399
Held-to-maturity, 12 months or more, unrealized losses		(52)
Residential Mortgage Backed Securities [Member]
Schedule Of Investments [Line Items]
Available-for-sale, less than 12 months, fair value	2,334	17,340
Available-for-sale, less than 12 months, unrealized losses	(1)	(66)
Available-for-sale, 12 months or more, fair value	1,019	10,094
Available-for-sale, 12 months or more, unrealized losses	(7)	(143)
Commercial Mortgage Backed Securities [Member]
Schedule Of Investments [Line Items]
Available-for-sale, less than 12 months, fair value	2,630	3,794
Available-for-sale, less than 12 months, unrealized losses	(1)	(25)
Available-for-sale, 12 months or more, fair value	3,327	29,754
Available-for-sale, 12 months or more, unrealized losses	(141)	(361)
Held-to-maturity, less than 12 months, fair value	412	685
Held-to-maturity, 12 months or more, fair value		6,405
Held-to-maturity, 12 months or more, unrealized losses		(46)
US Treasury Securities [Member]
Schedule Of Investments [Line Items]
Available-for-sale, less than 12 months, fair value	10,077	80
Available-for-sale, less than 12 months, unrealized losses	$ (1)
US Government Agencies Debt Securities [Member]
Schedule Of Investments [Line Items]
Held-to-maturity, less than 12 months, fair value		846
Held-to-maturity, less than 12 months, unrealized losses		(4)
Held-to-maturity, 12 months or more, fair value		2,994
Held-to-maturity, 12 months or more, unrealized losses		$ (6)

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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