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Nature of Business and Basis of Presentation - Additional Information (Detail)	6 Months Ended
	Jun. 30, 2020 USD ($) Employee Segment	Dec. 31, 2019 USD ($)
Organization, Consolidation and Presentation of Financial Statements Disclosure [Line Items]
Number of operating segments | Segment	1
Total current assets	$ 827,611,000	$ 855,005,000
Cash and cash equivalents	214,007,000	644,588,000
Short-term investments	336,273,000
Long-term investments	61,039,000
Accounts receivable, net	124,985,000	116,430,000
Inventory	124,844,000	$ 76,769,000
Other debt outstanding	$ 0
Sales Representatives and Managers
Organization, Consolidation and Presentation of Financial Statements Disclosure [Line Items]
Number of sales professionals | Employee	440
Sales Representatives
Organization, Consolidation and Presentation of Financial Statements Disclosure [Line Items]
Number of sales professionals | Employee	400
Direct Sales Force
Organization, Consolidation and Presentation of Financial Statements Disclosure [Line Items]
Number of sales professionals | Employee	900
Direct Sales Force And Sales Representatives
Organization, Consolidation and Presentation of Financial Statements Disclosure [Line Items]
Number of sales professionals | Employee	800

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