Intangible assets (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Finite-Lived Intangible Assets [Line Items]
Amortization of Intangible Assets	$ 700	$ 400
Finite-Lived Intangible Assets, Gross	15,668		$ 15,204
Finite-Lived Intangible Assets, Accumulated Amortization	(2,773)		(2,092)
Finite-Lived Intangible Assets, Net	12,895		13,112
Trade Names [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	8,367		8,090
Finite-Lived Intangible Assets, Accumulated Amortization	(1,741)		(1,447)
Finite-Lived Intangible Assets, Net	6,626		6,643
Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	7,301		7,114
Finite-Lived Intangible Assets, Accumulated Amortization	(1,032)		(645)
Finite-Lived Intangible Assets, Net	$ 6,269		$ 6,469