Property, plant and equipment (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Property, plant and equipment [Abstract]
Property, plant and equipment, gross	$ 595,459	$ 539,584
Less: Accumulated depreciation and amortization	(160,384)	(132,374)
Total Property, plant and equipment, net	435,075	407,210
Land and Improvements [Member]
Property, plant and equipment [Abstract]
Property, plant and equipment, gross	21,848	21,843
Buildings, Building Improvements and Leasehold Improvements [Member]
Property, plant and equipment [Abstract]
Property, plant and equipment, gross	161,175	160,005
Furniture and Equipment [Member]
Property, plant and equipment [Abstract]
Property, plant and equipment, gross	217,908	206,819
Software [Member]
Property, plant and equipment [Abstract]
Property, plant and equipment, gross	53,180	50,829
Construction-In-Progress [Member]
Property, plant and equipment [Abstract]
Property, plant and equipment, gross	$ 141,348	$ 100,088

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

+ References

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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.

+ References

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