Securities, Held-to-maturity Securities (Details) Unit13 in Thousands, $ in Thousands	Mar. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Amortized cost and fair value of investment securities held to maturity [Abstract]
Amortized Cost	$ 35,793	$ 38,912
Unrealized Gains	83	68
Unrealized Losses	478	768
Fair Value	$ 35,398	$ 38,212
Debt Securities, Held-to-maturity, Continuous Unrealized Loss Number Of Position[Abstract]
12 Months or Longer Securities	26	28
Total Securities	26	28
Fair Value [Abstract]
12 Months or More, Fair Value	$ 31,112	$ 33,938
Total, Estimated Fair Value	31,112	33,938
Unrealized Losses [Abstract]
12 Months or More, Unrealized Losses	478	768
Total, Unrealized Losses	478	768
U.S. Treasury Securities [Member]
Amortized cost and fair value of investment securities held to maturity [Abstract]
Amortized Cost	1,991	1,991
Unrealized Gains	17	17
Fair Value	2,008	2,008
U.S. Government Agency Notes [Member]
Amortized cost and fair value of investment securities held to maturity [Abstract]
Amortized Cost	9,991	11,992
Unrealized Gains	58	45
Unrealized Losses	63	92
Fair Value	$ 9,986	$ 11,945
Debt Securities, Held-to-maturity, Continuous Unrealized Loss Number Of Position[Abstract]
12 Months or Longer Securities	8	10
Total Securities	8	10
Fair Value [Abstract]
12 Months or More, Fair Value	$ 7,953	$ 9,927
Total, Estimated Fair Value	7,953	9,927
Unrealized Losses [Abstract]
12 Months or More, Unrealized Losses	63	92
Total, Unrealized Losses	63	92
Mortgage-backed Securities [Member]
Amortized cost and fair value of investment securities held to maturity [Abstract]
Amortized Cost	23,811	24,929
Unrealized Gains	8	6
Unrealized Losses	415	676
Fair Value	$ 23,404	$ 24,259
Debt Securities, Held-to-maturity, Continuous Unrealized Loss Number Of Position[Abstract]
12 Months or Longer Securities	18	18
Total Securities	18	18
Fair Value [Abstract]
12 Months or More, Fair Value	$ 23,159	$ 24,011
Total, Estimated Fair Value	23,159	24,011
Unrealized Losses [Abstract]
12 Months or More, Unrealized Losses	415	676
Total, Unrealized Losses	$ 415	$ 676

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Amount of investment in debt security measured at amortized cost (held-to-maturity).

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