Investment (Gross Unrealized Losses and Fair Values of Securities) (Details) $ in Thousands	Mar. 31, 2020 USD ($) item	Dec. 31, 2019 USD ($) item
Schedule of Investments [Line Items]
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	$ 2,683	$ 34,430
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Unrealized Losses	$ 29	$ 134
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Number of Investments \| item	1	6
Available-for-Sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	$ 13,739	$ 70,605
Available-for-Sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Unrealized Losses	$ 6,098	$ 4,266
Available-for-Sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Investments \| item	10	16
Held-to-Maturity Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value		$ 2,722
Held-to-Maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Unrealized Losses		$ 6
Held-to-Maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Number Of Investments \| item		3
Held-to-Maturity Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	$ 596	$ 9,486
Held-to-Maturity Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Unrealized Losses	$ 4	$ 149
Held-to-Maturity Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Number Of Investments \| item	2	12
US government agencies [Member]
Schedule of Investments [Line Items]
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value		$ 24,907
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Unrealized Losses		$ 80
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Number of Investments \| item		3
Available-for-Sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value		$ 14,987
Available-for-Sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Unrealized Losses		$ 13
Available-for-Sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Investments \| item		3
Residential mortgage-backed agencies [Member]
Schedule of Investments [Line Items]
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value		$ 4,900
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Unrealized Losses		$ 17
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Number of Investments \| item		1
Held-to-Maturity Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value		$ 2,722
Held-to-Maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Unrealized Losses		$ 6
Held-to-Maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Number Of Investments \| item		3
Held-to-Maturity Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	$ 596	$ 9,486
Held-to-Maturity Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Unrealized Losses	$ 4	$ 149
Held-to-Maturity Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Number Of Investments \| item	2	12
Commercial mortgage-backed agencies [Member]
Schedule of Investments [Line Items]
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	$ 2,683	$ 4,623
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Unrealized Losses	$ 29	$ 37
Available-for-Sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Number of Investments \| item	1	2
Available-for-Sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	$ 1,359	$ 5,793
Available-for-Sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Unrealized Losses	$ 8	$ 55
Available-for-Sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Investments \| item	1	3
Collateralized mortgage obligations [Member]
Schedule of Investments [Line Items]
Available-for-Sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value		$ 35,472
Available-for-Sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Unrealized Losses		$ 109
Available-for-Sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Investments \| item		1
Collateralized debt obligations [Member]
Schedule of Investments [Line Items]
Available-for-Sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	$ 12,380	$ 14,353
Available-for-Sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Unrealized Losses	$ 6,090	$ 4,089
Available-for-Sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Investments \| item	9	9

Held To Maturity Securities In Unrealized Loss Positions 12 Months Or Longer Number Of Positions

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