Restructuring and asset impairment - Restructuring Accrual Activity for Given Years (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Restructuring Reserve [Roll Forward]
Liability, beginning balance	$ 7,572	$ 7,146
Charges	44,819	40,071	$ 19,834
Cash receipts/(payments)	(26,144)	(6,819)
Asset write downs/disposals	(14,899)	(32,759)
Foreign currency translation	9	(67)
Liability, ending balance	11,357	7,572	7,146
Severance and Termination Benefits
Restructuring Reserve [Roll Forward]
Liability, beginning balance	5,293	5,982
Charges	24,864	15,224	12,684
Cash receipts/(payments)	(19,386)	(15,844)
Asset write downs/disposals	0	0
Foreign currency translation	(6)	(69)
Liability, ending balance	10,765	5,293	5,982
Asset Impairment/Disposal of Assets
Restructuring Reserve [Roll Forward]
Liability, beginning balance	0	0
Charges	9,674	6,193	120
Cash receipts/(payments)	5,225	26,566
Asset write downs/disposals	(14,899)	(32,759)
Foreign currency translation	0	0
Liability, ending balance	0	0	0
Other Costs
Restructuring Reserve [Roll Forward]
Liability, beginning balance	2,279	1,164
Charges	10,281	18,654
Cash receipts/(payments)	(11,983)	(17,541)
Asset write downs/disposals	0	0
Foreign currency translation	15	2
Liability, ending balance	$ 592	$ 2,279	$ 1,164

Payments For (Proceeds From) Restructuring

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- Definition

Restructuring reserve asset write offs.

+ References

No definition available.

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- Definition

Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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- Definition

Carrying amount as of the balance sheet date of known and estimated obligations associated with exit from or disposal of business activities or restructurings pursuant to a duly authorized plan, which are expected to be paid in the next twelve months or in the normal operating cycle if longer. Costs of such activities include those for one-time termination benefits, termination of an operating lease or other contract, consolidating or closing facilities, relocating employees, and costs associated with an ongoing benefit arrangement, but excludes costs associated with the retirement of a long-lived asset.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

Amount of foreign currency translation gain (loss) which decreases (increases) the restructuring reserve.

+ References

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-Publisher FASB
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