Investment Securities (Amortized Cost and Fair Value of Investment Securities) (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Schedule of Held-to-maturity Securities And Available-for-sale Securities [Line Items]
Amortized cost: Total available-for-sale debt securities	$ 435,150	$ 381,088
Gross unrealized gains: Available-for-sale debt securities	8,501	11,753
Gross unrealized losses: Available-for-sale debt securities	(7,029)	(421)
Fair value: Available-for-sale debt securities	436,622	392,420
Agency - GSE [Member]
Schedule of Held-to-maturity Securities And Available-for-sale Securities [Line Items]
Amortized cost: Total available-for-sale debt securities	58,792	45,146
Gross unrealized gains: Available-for-sale debt securities	336	392
Gross unrealized losses: Available-for-sale debt securities	(2,278)	(91)
Fair value: Available-for-sale debt securities	56,850	45,447
Obligations Of States And Political Subdivisions [Member]
Schedule of Held-to-maturity Securities And Available-for-sale Securities [Line Items]
Amortized cost: Total available-for-sale debt securities	226,443	192,385
Gross unrealized gains: Available-for-sale debt securities	5,118	7,480
Gross unrealized losses: Available-for-sale debt securities	(3,400)	(152)
Fair value: Available-for-sale debt securities	228,161	199,713
MBS - GSE Residential [Member]
Schedule of Held-to-maturity Securities And Available-for-sale Securities [Line Items]
Amortized cost: Total available-for-sale debt securities	149,915	143,557
Gross unrealized gains: Available-for-sale debt securities	3,047	3,881
Gross unrealized losses: Available-for-sale debt securities	(1,351)	(178)
Fair value: Available-for-sale debt securities	$ 151,611	$ 147,260

Schedule of Held-to-maturity Securities And Available-for-sale Securities [Line Items]

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Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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