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Business - Additional Information (Detail) | 9 Months Ended
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Sep. 30, 2018 country
Product Information [Line Items] |
Number of countries company operates | 31
Sales Revenue Outside United States | Customer Concentration Risk |
Product Information [Line Items] |
Percent of revenue from customers outside the U.S. (as a percent) | 66.00%
Minimum |
Product Information [Line Items] |
Number of countries where product is found (more than) | 100

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