Property and equipment, net - Property and equipment, net (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Property and equipment, net
Property and Equipment, gross	$ 584,213	$ 499,437
Less accumulated depreciation and amortization	(130,436)	(121,870)
Property and Equipment, net	453,777	377,567
Office equipment
Property and equipment, net
Property and Equipment, gross	14,482	15,303
Laboratory equipment
Property and equipment, net
Property and Equipment, gross	72,915	70,510
Computer equipment
Property and equipment, net
Property and Equipment, gross	59,642	59,069
Land
Property and equipment, net
Property and Equipment, gross	10,294	10,203
Building and leasehold improvements
Property and equipment, net
Property and Equipment, gross	206,498	208,293
Operating lease right-of-use assets
Property and equipment, net
Property and Equipment, gross	23,532	19,672
Construction in Progress
Property and equipment, net
Property and Equipment, gross	$ 196,850	$ 116,387

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.

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