Securities, Held-to-maturity Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Amortized cost and fair value of investment securities held to maturity [Abstract]
Amortized Cost	$ 22,737	$ 25,960
Unrealized Gains	723	228
Unrealized Losses	3	30
Fair Value	$ 23,457	$ 26,158
Debt Securities, Held-to-maturity, Continuous Unrealized Loss Number Of Position[Abstract]
Less than 12 Months Securities	1	2
12 Months or Longer Securities		5
Total Securities	1	7
Fair Value [Abstract]
Less than 12 Months, Fair Value	$ 148	$ 2,544
12 Months or More, Fair Value		4,241
Total, Estimated Fair Value	148	6,785
Unrealized Losses [Abstract]
Less than 12 Months, Unrealized Losses	3	17
12 Months or More, Unrealized Losses		13
Total, Unrealized Losses	3	30
U.S. Treasury Securities [Member]
Amortized cost and fair value of investment securities held to maturity [Abstract]
Amortized Cost	996	994
Unrealized Gains	19	14
Fair Value	1,015	1,008
U.S. Government Agency Notes [Member]
Amortized cost and fair value of investment securities held to maturity [Abstract]
Amortized Cost	2,985	4,986
Unrealized Gains	156	100
Unrealized Losses		5
Fair Value	$ 3,141	$ 5,081
Debt Securities, Held-to-maturity, Continuous Unrealized Loss Number Of Position[Abstract]
Less than 12 Months Securities	1
12 Months or Longer Securities		3
Total Securities	1	3
Fair Value [Abstract]
Less than 12 Months, Fair Value	$ 148
12 Months or More, Fair Value		$ 3,003
Total, Estimated Fair Value	148	3,003
Unrealized Losses [Abstract]
Less than 12 Months, Unrealized Losses	3
12 Months or More, Unrealized Losses		5
Total, Unrealized Losses	3	5
Mortgage-backed Securities [Member]
Amortized cost and fair value of investment securities held to maturity [Abstract]
Amortized Cost	18,756	19,980
Unrealized Gains	548	114
Unrealized Losses	3	25
Fair Value	$ 19,301	$ 20,069
Debt Securities, Held-to-maturity, Continuous Unrealized Loss Number Of Position[Abstract]
Less than 12 Months Securities		2
12 Months or Longer Securities		2
Total Securities		4
Fair Value [Abstract]
Less than 12 Months, Fair Value		$ 2,544
12 Months or More, Fair Value		1,238
Total, Estimated Fair Value		3,782
Unrealized Losses [Abstract]
Less than 12 Months, Unrealized Losses		17
12 Months or More, Unrealized Losses		8
Total, Unrealized Losses		$ 25

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