Revenue - Information about Receivables, Contract Assets, and Unearned Revenue from Contracts with Customers (Detail) - USD ($) $ in Thousands	Sep. 30, 2020	Jan. 01, 2020	Dec. 31, 2019
Revenue From Contract With Customer [Abstract]
Accounts receivable, net	$ 100,223	$ 90,500	$ 90,531
Contract assets	1,015	$ 2,800	2,812
Unearned revenue	13,379		11,963
Non-current unearned revenue	$ 6,694		$ 6,012

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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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