Securities, Securities Available for Sale by Contractual Maturity (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2018 USD ($) Security	Mar. 31, 2017 USD ($) Security	Dec. 31, 2017 USD ($)
Amortized Cost [Abstract]
Due in one year or less	$ 2,007
Due after one year through five years	4,358
Due after five years through ten years	24,239
Due after ten years	39,825
Mutual funds	388
Amortized cost	70,817		$ 72,198
Fair Value [Abstract]
Due in one year or less	2,001
Due after one year through five years	4,259
Due after five years through ten years	23,712
Due after ten years	39,333
Mutual funds	378
Total fair value	$ 69,683		$ 72,153
Number of securities sold | Security	0	0
Proceeds from calls and principal repayments	$ 3,766	$ 4,077
Fair value of securities purchased	2,000	10,000
Impairment losses on securities	$ 0	$ 0