Investment Securities - Total investment securities (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Contractual maturities of securities
Available for Sale, Cost Basis, Within 1 year	$ 2,500
Available for Sale, Cost Basis, After 1 year but within 5 years	21,374
Available for Sale, Cost Basis, After 5 years but within 10 years	40,360
Available for Sale, Cost Basis, After 10 years but within 15 years	24,722
Available for Sale, Cost Basis, Over 15 years	52,154
Available for Sale, Cost Basis, Total	141,110	$ 148,514
Available for Sale, Fair Value, Within 1 year	2,506
Available for Sale, Fair Value, After 1 year but within 5 years	21,485
Available for Sale, Fair Value, After 5 years but within 10 years	41,005
Available for Sale, Fair Value, After 10 years but within 15 years	25,248
Available for Sale, Fair Value, Over 15 years	53,156
Available for Sale, Fair Value, Total	143,400	146,731
Held to Maturity, Cost Basis, Within 1 year	0
Held to Maturity, Cost Basis, After 1 year but within 5 years	6,516
Held to Maturity, Cost Basis, After 5 years but within 10 years	19,662
Held to Maturity, Cost Basis, After 10 years but within 15 years	8,085
Held to Maturity, Cost Basis, Over 15 years	5,036
Held to Maturity, Cost Basis, Total	39,299	40,760
Held to Maturity, Fair Value, Within 1 year	0
Held to Maturity, Fair Value, After 1 year but within 5 years	6,565
Held to Maturity, Fair Value, After 5 years but within 10 years	20,618
Held to Maturity, Fair Value, After 10 years but within 15 years	8,481
Held to Maturity, Fair Value, Over 15 years	5,149
Held to Maturity, Fair Value, Total	$ 40,813	$ 40,324

Available For Sale And Held For Maturity Securities Debt Maturities Amortized Cost

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