Fair Value Measurements (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2018	Dec. 31, 2017
Fair value measurements
Earn-out payments paid	$ 0	$ 0
Reconciliation of the beginning and ending balance for the Level 3 measurement
Balance at the beginning of the period		133
Additions		67
Balance at the end of the period	200	200
Recurring basis
Fair value measurements
Contingent Consideration	200	200	$ 133
Recurring basis | Level 3
Fair value measurements
Contingent Consideration	$ 200	$ 200	$ 133