Property and Equipment (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	$ 104,616	$ 102,045
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment	(50,919)	(48,797)
Property, Plant and Equipment, Net	53,697	53,248
Land
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	3,828	3,828
Building and improvements
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	24,059	24,060
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	483	483
Machinery and equipment
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	17,345	17,239
Revenue-generating assets
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	44,442	42,424
Office and computer equipment
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	14,428	13,980
Motor vehicles
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	$ 31	$ 31