Investments (Gross Unrealized Losses and Fair Values of Securities) (Details) - USD ($)	Jun. 30, 2021	Dec. 31, 2020
Schedule of Investments [Line Items]
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	$ 155,868,000	$ 118,172,000
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Unrealized Losses	$ 4,518,000	$ 459,000
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Number of Investments	19	14
Available-for-Sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	$ 16,230,000	$ 13,260,000
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Unrealized Losses	$ 2,349,000	$ 5,284,000
Available-for-Sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Investments	9	9
Held-to-Maturity Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	$ 8,268,000	$ 2,973,000
Held-to-Maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Unrealized Losses	$ 327,000	$ 38,000
Held-to-Maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Number Of Investments	3	1
U.S. government agencies [Member]
Schedule of Investments [Line Items]
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	$ 34,409,000	$ 39,611,000
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Unrealized Losses	$ 1,949,000	$ 322,000
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Number of Investments	6	7
Residential mortgage-backed agencies [Member]
Schedule of Investments [Line Items]
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	$ 31,481,000	$ 22,899,000
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Unrealized Losses	$ 545,000	$ 100,000
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Number of Investments	3	2
Held-to-Maturity Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	$ 8,268,000	$ 2,973,000
Held-to-Maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Unrealized Losses	$ 327,000	$ 38,000
Held-to-Maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Number Of Investments	3	1
Commercial mortgage-backed agencies [Member]
Schedule of Investments [Line Items]
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	$ 24,748,000	$ 16,034,000
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Unrealized Losses	$ 477,000	$ 36,000
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Number of Investments	3	1
Collateralized mortgage obligations [Member]
Schedule of Investments [Line Items]
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	$ 65,230,000	$ 39,628,000
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Unrealized Losses	$ 1,547,000	$ 1,000
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Number of Investments	7	4
Collateralized debt obligations [Member]
Schedule of Investments [Line Items]
Available-for-Sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	$ 16,230,000	$ 13,260,000
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Unrealized Losses	$ 2,349,000	$ 5,284,000
Available-for-Sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Investments	9	9

Held To Maturity Securities In Unrealized Loss Positions Less Than 12 Months Number Of Positions

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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 more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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