Intangible assets Schedule of intangibles (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	$ 15,204	$ 13,093
Finite-Lived Intangible Assets, Accumulated Amortization	(2,092)	(1,280)
Finite-Lived Intangible Assets, Net	13,112	11,813
Trade Names [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	8,090	8,182
Finite-Lived Intangible Assets, Accumulated Amortization	(1,447)	(957)
Finite-Lived Intangible Assets, Net	6,643	7,225
Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	7,114	4,911
Finite-Lived Intangible Assets, Accumulated Amortization	(645)	(323)
Finite-Lived Intangible Assets, Net	$ 6,469	$ 4,588