Employee Benefit Plan - Defined Contribution Plan (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
US
Defined contribution pension plan
Employer match, contributions	$ 0.3	$ 0.3	$ 0.2

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.

No definition available.

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