Securities, Securities Available for Sale by Contractual Maturity (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2018 USD ($) Security	Jun. 30, 2017 USD ($) Security	Dec. 31, 2017 USD ($)
Amortized Cost [Abstract]
Due in one year or less	$ 2,003
Due after one year through five years	4,316
Due after five years through ten years	26,594
Due after ten years	41,614
Amortized cost	74,527		$ 72,198
Fair Value [Abstract]
Due in one year or less	1,999
Due after one year through five years	4,208
Due after five years through ten years	25,911
Due after ten years	40,961
Total fair value	$ 73,079		$ 72,153
Number of securities sold | Security	0	0
Proceeds from calls and principal repayments	$ 7,376	$ 7,614
Fair value of securities purchased	9,400	20,500
Impairment losses on securities	$ 0	$ 0