Restructurings - Components of Restructuring Expense (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Restructuring Cost and Reserve [Line Items]
Total restructuring expense	$ 0	$ 398	$ 592	$ 398
Operating expenses — restructuring:
Restructuring Cost and Reserve [Line Items]
Employee severance and benefits	$ 0	$ 398	$ 592	$ 398

Amount of expenses for special or contractual termination benefits provided to current employees involuntarily terminated under a benefit arrangement associated exit or disposal activities pursuant to an authorized plan. Excludes expenses related to one-time termination benefits, a discontinued operation or an asset retirement obligation.

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