Investment Securities - Securities in Continuous Unrealized Loss Position (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Schedule Of Investments [Line Items]
Available-for-sale, less than 12 months, fair value	$ 7,049	$ 21,214
Available-for-sale, less than 12 months, unrealized losses	(13)	(91)
Available-for-sale, 12 months or more, fair value	4,481	39,848
Available-for-sale, 12 months or more, unrealized losses	(213)	(504)
Held-to-maturity, less than 12 months, fair value	771	1,531
Held-to-maturity, less than 12 months, unrealized losses	(4)	(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	1,414	17,340
Available-for-sale, less than 12 months, unrealized losses	(6)	(66)
Available-for-sale, 12 months or more, fair value	866	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	4,415	3,794
Available-for-sale, less than 12 months, unrealized losses	(6)	(25)
Available-for-sale, 12 months or more, fair value	3,469	29,754
Available-for-sale, 12 months or more, unrealized losses	(206)	(361)
Held-to-maturity, less than 12 months, fair value	771	685
Held-to-maturity, less than 12 months, unrealized losses	(4)
Held-to-maturity, 12 months or more, fair value		6,405
Held-to-maturity, 12 months or more, unrealized losses		(46)
US States and Political Subdivisions Debt Securities [Member]
Schedule Of Investments [Line Items]
Available-for-sale, less than 12 months, fair value	1,139
Available-for-sale, less than 12 months, unrealized losses	(1)
Available-for-sale, 12 months or more, fair value	146
US Treasury Securities [Member]
Schedule Of Investments [Line Items]
Available-for-sale, less than 12 months, fair value	$ 81	80
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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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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Amount of accumulated unrealized loss on investment in debt security measured at amortized cost (held-to-maturity), in continuous loss position for 12 months or longer.

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