Ransomware incident (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Ransomware incident
Ransomware related incident costs, net	$ (1,558)	$ 0	$ (1,305)	$ 0	$ 7,700
Insurance recoveries					$ 5,000
Collection of recorded insurance receivable			$ 6,600

The amount of costs (recovery) associated with systems affected by a ransomware incident that encrypted information on our systems and disrupted customer and employee access to our systems and services.

No definition available.

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- References

No definition available.

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- Definition

The increase (decrease) during the reporting period in insurance settlements receivable, which are amounts due in settlement of a claim for reimbursement from an insurance company when the Company has suffered a loss covered under an insurance policy. The expectation is that such reimbursement will be received within one year of the balance sheet date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3602-108585

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- Definition

The amount recovered from insurance. These recoveries reduce costs and losses that are reported as a separate line item under operating expenses.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.3)
-URI http://asc.fasb.org/extlink&oid=120395209&loc=SL114868664-224227

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