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Segment Information and Major Customers - Additional Information (Detail) $ in Millions	12 Months Ended
	Dec. 31, 2020 USD ($) Customer Category Segment	Dec. 31, 2019 USD ($) Customer	Dec. 31, 2018 Customer
Segment Reporting Information [Line Items]
Number of reportable segments | Segment	2
Number of categories | Category	3
Number of single customer comprising more than 10% of sales | Customer	3	3	2
Long-lived assets	$ 62.4	$ 68.1
U.S. [Member]
Segment Reporting Information [Line Items]
Long-lived assets	58.4	64.2
Outside U.S. [Member]
Segment Reporting Information [Line Items]
Long-lived assets	$ 4.0	$ 3.9
Sales Revenue, Net [Member] | Customer Concentration Risk [Member] | Customer 1 [Member]
Segment Reporting Information [Line Items]
Concentration risk, percentage	15.00%	19.00%	27.00%
Sales Revenue, Net [Member] | Customer Concentration Risk [Member] | Customer 2 [Member]
Segment Reporting Information [Line Items]
Concentration risk, percentage	12.00%	17.00%	17.00%
Sales Revenue, Net [Member] | Customer Concentration Risk [Member] | Customer 3 [Member]
Segment Reporting Information [Line Items]
Concentration risk, percentage	10.00%	13.00%
Sales Revenue, Net [Member] | Customer Concentration Risk [Member] | The Five Largest Customers Other Than Those With More Than 10% Of Revenues and Excluding Distributors [Member]
Segment Reporting Information [Line Items]
Concentration risk, percentage	19.00%	15.00%	18.00%

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Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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