Revenue Recognition (Additional Information) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Accumulated deficit	$ (553,764)		$ (553,764)		$ (544,010)
Revenue	40,424	$ 44,248	83,569	$ 83,720
Long-term accounts receivable	400		400		300
Deferred revenue	$ 6,600		$ 6,600		$ 6,700

Amount, after allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as noncurrent.

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