Securities - Schedule of Marketable Securities by Contractual Maturity (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Available for sale at fair value:
Available for sale at fair value, Within one year	$ 23
Available for sale at fair value yield, Within one year	3.48%
Available for sale at fair value, After one through five years	$ 8,539
Available for sale at fair value yield, After one through five years	2.44%
Available for sale at fair value, After five through ten years	$ 12,706
Available for sale at fair value yield, After five through ten years	3.40%
Available for sale at fair value, After ten years	$ 25,606
Available for sale at fair value yield, After ten years	2.83%
Available-for-sale Securities	$ 46,874
Available for sale at fair value yield	2.92%
Held to maturity at cost:
Held to maturity at cost, Within one year	$ 0
Held to maturity at cost yield, Within one year	0.00%
Held to maturity at cost, After one through five years	$ 54
Held to maturity at cost yield, After one through five years	5.23%
Held to maturity at cost, After five through ten years	$ 5,417
Held to maturity at cost yield, After five through ten years	5.43%
Held to maturity at cost, After ten years	$ 9,854
Held to maturity at cost yield, After ten years	2.74%
Amortized cost	$ 15,325	$ 16,307
Held to maturity at cost yield,	3.70%
Equity securities:
Equity securities at cost, Within one year	$ 0
Equity securities at cost yield, Within one year	0.00%
Equity securities at cost, After one through five years	$ 0
Equity securities at cost yield, After one through five years	0.00%
Equity securities at cost, After five through ten years	$ 0
Equity securities at cost yield, After five through ten years	0.00%
Equity securities at cost, After ten years	$ 1,200
Equity securities at cost yield, after ten years	2.04%
Equity securities	$ 1,200	1,206
Equity securities yield	2.04%
U.S. Government sponsored entities
Available for sale at fair value:
Available for sale at fair value, Within one year	$ 0
Available for sale at fair value yield, Within one year	0.00%
Available for sale at fair value, After one through five years	$ 3,646
Available for sale at fair value yield, After one through five years	1.61%
Available for sale at fair value, After five through ten years	$ 1,931
Available for sale at fair value yield, After five through ten years	2.17%
Available for sale at fair value, After ten years	$ 0
Available for sale at fair value yield, After ten years	0.00%
Available-for-sale Securities	$ 5,577	5,691
Available for sale at fair value yield	1.80%
Held to maturity at cost:
Held to maturity at cost, Within one year	$ 0
Held to maturity at cost yield, Within one year	0.00%
Held to maturity at cost, After one through five years	$ 0
Held to maturity at cost yield, After one through five years	0.00%
Held to maturity at cost, After five through ten years	$ 0
Held to maturity at cost yield, After five through ten years	0.00%
Held to maturity at cost, After ten years	$ 2,789
Held to maturity at cost yield, After ten years	1.98%
Amortized cost	$ 2,789	3,026
Held to maturity at cost yield,	1.98%
State and political subdivisions
Available for sale at fair value:
Available for sale at fair value, Within one year	$ 0
Available for sale at fair value yield, Within one year	0.00%
Available for sale at fair value, After one through five years	$ 1,151
Available for sale at fair value yield, After one through five years	3.43%
Available for sale at fair value, After five through ten years	$ 1,674
Available for sale at fair value yield, After five through ten years	2.41%
Available for sale at fair value, After ten years	$ 1,834
Available for sale at fair value yield, After ten years	2.69%
Available-for-sale Securities	$ 4,659	5,192
Available for sale at fair value yield	2.77%
Held to maturity at cost:
Held to maturity at cost, Within one year	$ 0
Held to maturity at cost yield, Within one year	0.00%
Held to maturity at cost, After one through five years	$ 0
Held to maturity at cost yield, After one through five years	0.00%
Held to maturity at cost, After five through ten years	$ 494
Held to maturity at cost yield, After five through ten years	5.07%
Held to maturity at cost, After ten years	$ 457
Held to maturity at cost yield, After ten years	5.84%
Amortized cost	$ 951	1,113
Held to maturity at cost yield,	5.44%
Residential mortgage-backed securities
Available for sale at fair value:
Available for sale at fair value, Within one year	$ 23
Available for sale at fair value yield, Within one year	3.48%
Available for sale at fair value, After one through five years	$ 640
Available for sale at fair value yield, After one through five years	1.98%
Available for sale at fair value, After five through ten years	$ 2,890
Available for sale at fair value yield, After five through ten years	2.37%
Available for sale at fair value, After ten years	$ 23,772
Available for sale at fair value yield, After ten years	2.84%
Available-for-sale Securities	$ 27,325	31,878
Available for sale at fair value yield	2.77%
Held to maturity at cost:
Held to maturity at cost, Within one year	$ 0
Held to maturity at cost yield, Within one year	0.00%
Held to maturity at cost, After one through five years	$ 54
Held to maturity at cost yield, After one through five years	5.23%
Held to maturity at cost, After five through ten years	$ 406
Held to maturity at cost yield, After five through ten years	2.48%
Held to maturity at cost, After ten years	$ 3,009
Held to maturity at cost yield, After ten years	2.98%
Amortized cost	$ 3,469	3,958
Held to maturity at cost yield,	2.96%
Commercial mortgage-backed securities
Held to maturity at cost:
Held to maturity at cost, Within one year	$ 0
Held to maturity at cost yield, Within one year	0.00%
Held to maturity at cost, After one through five years	$ 0
Held to maturity at cost yield, After one through five years	0.00%
Held to maturity at cost, After five through ten years	$ 0
Held to maturity at cost yield, After five through ten years	0.00%
Held to maturity at cost, After ten years	$ 3,599
Held to maturity at cost yield, After ten years	2.73%
Amortized cost	$ 3,599	3,685
Held to maturity at cost yield,	2.73%
Corporate and other securities
Available for sale at fair value:
Available for sale at fair value, Within one year	$ 0
Available for sale at fair value yield, Within one year	0.00%
Available for sale at fair value, After one through five years	$ 3,102
Available for sale at fair value yield, After one through five years	3.14%
Available for sale at fair value, After five through ten years	$ 6,211
Available for sale at fair value yield, After five through ten years	4.54%
Available for sale at fair value, After ten years	$ 0
Available for sale at fair value yield, After ten years	0.00%
Available-for-sale Securities	$ 9,313	10,732
Available for sale at fair value yield	4.07%
Held to maturity at cost:
Held to maturity at cost, Within one year	$ 0
Held to maturity at cost yield, Within one year	0.00%
Held to maturity at cost, After one through five years	$ 0
Held to maturity at cost yield, After one through five years	0.00%
Held to maturity at cost, After five through ten years	$ 4,517
Held to maturity at cost yield, After five through ten years	5.73%
Held to maturity at cost, After ten years	$ 0
Held to maturity at cost yield, After ten years	0.00%
Amortized cost	$ 4,517	$ 4,525
Held to maturity at cost yield,	5.73%