Leases - Adoption of new lease standard (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
ASSETS
Property, plant and equipment, net	$ 54,240	$ 52,525
Operating lease right of use assets	20,582	20,785
Other non-current assets	3,268	3,214
LIABILITIES
Current portion of operating leases	4,770	4,619
Operating leases, less current installments	16,283	16,580
Finance leases, less current installments	3,225	3,331
Other non-current liabilities	58	$ 117
Current portion of finance lease	$ 1,591

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Present value of lessee's discounted obligation for lease payments from finance lease, classified as current.

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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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