Property and equipment (Held for Sale Asset) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Property, Plant and Equipment [Line Items]
Held for sale assets	$ 2,860	$ 0
Equipment
Property, Plant and Equipment [Line Items]
Held for sale assets	1,572
Vehicles
Property, Plant and Equipment [Line Items]
Held for sale assets	488
Real estate
Property, Plant and Equipment [Line Items]
Held for sale assets	$ 800