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Concentrations - Additional Information (Detail) |  |  | 3 Months Ended
--- | --- | --- | ---
Mar. 31, 2019 | Dec. 31, 2018 | Mar. 31, 2019 | Mar. 31, 2018
Accounts Receivable | Customer Concentration Risk | Three Customers |  |  |  |
Concentration Risk [Line Items] |  |  |  |
Concentration risk, percentage |  | 89.00% |  |
Accounts Receivable | Customer Concentration Risk | Four Customers |  |  |  |
Concentration Risk [Line Items] |  |  |  |
Concentration risk, percentage | 74.00% |  |  |
Revenue | Customer Concentration Risk | Three Customers |  |  |  |
Concentration Risk [Line Items] |  |  |  |
Concentration risk, percentage |  |  |  | 67.00%
Revenue | Customer Concentration Risk | Five Customers |  |  |  |
Concentration Risk [Line Items] |  |  |  |
Concentration risk, percentage |  |  | 65.00% |
Accounts Payables | Supplier Concentration Risk | Three Vendors |  |  |  |
Concentration Risk [Line Items] |  |  |  |
Concentration risk, percentage | 37.00% |  |  |
Accounts Payables | Supplier Concentration Risk | Two Vendors |  |  |  |
Concentration Risk [Line Items] |  |  |  |
Concentration risk, percentage |  | 16.00% |  |
Cost of Goods Sold | Supplier Concentration Risk | Three Suppliers |  |  |  |
Concentration Risk [Line Items] |  |  |  |
Concentration risk, percentage |  |  | 65.00% |
Cost of Goods Sold | Supplier Concentration Risk | One Supplier |  |  |  |
Concentration Risk [Line Items] |  |  |  |
Concentration risk, percentage |  |  |  | 37.00%

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