Investment Securities (Amortized Cost and Estimated Fair Value by Maturity Date) (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Schedule of Available-for-sale Securities [Line Items]
Available for sale, Amortized Cost, Due in one year or less	$ 8,001
Available for sale, Amortized Cost, Due after one year through five years	34,771
Available for sale, Amortized Cost, Due after five years through ten years	41,353
Available for sale, Amortized Cost, Due after ten years	103,697
Available-for-sale securities, Amortized Cost	187,822	$ 198,670
Available for sale, Estimated Fair Value, Due in one year or less	7,966
Available for sale, Estimated Fair Value, Due after one year through five years	33,969
Available for sale, Estimated Fair Value, Due after five years through ten years	40,242
Available for sale, Estimated Fair Value, Due after ten years	101,082
Available for sale, Estimated Fair Value, Total	183,259	196,955
Held to maturity securities, Amortized Cost, Due after one year through five years	901
Held to maturity securities, Amortized Cost, Due after five years through ten years	3,502
Held to maturity securities, Amortized Cost, Due after ten years	1,759
Held to maturity securities, Amortized Cost, Total	6,162	6,247
Held to maturity securities, Estimated Fair Value, Due after one year through five years	925
Held to maturity securities, Estimated Fair Value, Due after five years through ten years	3,540
Held to maturity securities, Estimated Fair Value, Due after ten years	1,758
Held-to-maturity securities, Estimated Fair Value, Total	$ 6,223	6,391
Equity [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities, Amortized Cost		666
Available for sale, Estimated Fair Value, Total		$ 658