Summary of Receivables and Deferred Revenue from Contracts with Customers (Detail) - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2020	Dec. 31, 2019
Balances from contracts with customers only:
Accounts receivable	$ 55,830	$ 43,068
Deferred revenue (included in accrued liabilities in the consolidated balance sheets)	10,141
Revenue recognized during the nine-month period ended September 30, 2020 relating to:
The beginning deferred revenue balance	3,133
Changes in pricing related to products or services satisfied in previous periods	$ 0

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 current.

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Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable.

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