Stock Compensation Plans (Details) $ / shares in Units, $ in Thousands	6 Months Ended
	Jun. 30, 2018 USD ($) $ / shares shares
Options Outstanding, January 1, 2018 | shares	86,900
Options Outstanding, Forfeited or cancelled | shares	0
Options Outstanding, Exercised | shares	(47,500)
Options Outstanding, Granted | shares	0
Options outstanding, June 30, 2018 | shares	39,400
Options Outstanding, Vested or expected to vest at June 30, 2018 | shares	39,400
Options Outstanding, Exercisable at June 30, 2018 | shares	23,900
Weighted Average Exercise Price, Outstanding, January 1, 2018 | $ / shares	$ 10.81
Weighted Average Exercise Price, Forfeited or cancelled | $ / shares	0
Weighted Average Exercise Price, Exercised | $ / shares	8.15
Weighted Average Exercise Price, Granted | $ / shares	0
Weighted Average Exercise Price, outstanding, June 30, 2018 | $ / shares	14.00
Weighted Average Exercise Price, Vested or expected to vest at June 30, 2018 | $ / shares	14.00
Weighted Average Exercise Price, Exercisable at June 30, 2018 | $ / shares	$ 12.22
Weighted Average Remaining Contractual Term (in years), outstanding, June 30, 2018	5 years 5 months 16 days
Weighted Average Remaining Contractual Term (in years), Vested or expected to vest at June 30, 2018	5 years 5 months 16 days
Weighted Average Remaining Contractual Term (in years), Exercisable at June 30, 2018	4 years 7 months 20 days
Aggregate Intrinsic Value, outstanding, June 30, 2018 | $	$ 770
Aggregate Intrinsic Value, Vested or expected to vest at June 30, 2018 | $	770
Aggregate Intrinsic Value, Exercisable at June 30, 2018 | $	$ 509