Commitments and contingencies - Additional Information (Details) - Pending Litigation - Civil Action Brought By Former Employee - USD ($) $ in Thousands	Sep. 30, 2019	May 03, 2019
Loss Contingencies [Line Items]
Damages sought	$ 4,272	$ 6,185
Estimate of possible loss	1,237
Loss contingency, receivable	1,237
Receivables due from related parties	$ 412

For an unclassified balance sheet, amounts due from related parties including affiliates, employees, joint ventures, officers and stockholders, immediate families thereof, and pension funds.

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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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No definition available.

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The value (monetary amount) of the award the plaintiff seeks in the legal matter.

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Reflects the estimated amount of loss from the specified contingency as of the balance sheet date.

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Amount of receivable related to a loss contingency accrual. For example, an insurance recovery receivable.

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