Property, plant and equipment, net - Narrative (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Property, Plant and Equipment [Line Items]
Finance lease ROU, before accumulated amortization	$ 22,981
Property, plant and equipment, net		$ 177,543
Finance lease ROU, after accumulated amortization	$ 12,947
Accumulated depreciation		39,365
Assets Held under Capital Leases
Property, Plant and Equipment [Line Items]
Property, plant and equipment, net		26,501
Accumulated depreciation		$ 4,670

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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Amount of accumulated amortization of right-of-use asset from finance lease.

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Amount, before accumulated amortization, of right-of-use asset from finance lease.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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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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