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Summary of Significant Accounting Policies - Additional Information (Detail) - USD ($) $ in Millions |  | 12 Months Ended
--- | --- | ---
Oct. 10, 2017 | Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Significant Accounting Policies [Line Items] |  |  |  |  |
Concentration risk, customer |  |  | two customers each accounted for 10% or more of the Company’s revenues | two customers each accounted for 10% or more of the Company’s revenues | two customers each accounted for 10% or more of the Company’s revenues
Options and warrants excluded from the calculation of diluted shares |  |  | 0 | 73,034 | 106,290
Production and importation permission description |  |  | 22 million pounds in 2015 and was reduced by approximately 4.5 million pounds each year ending at zero in 2020. |  |
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent |  |  | 35.00% | 35.00% | 34.00%
Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Amount |  |  | $ 1.4 |  |
Payables to Customers |  |  | 9.8 |  |
Business Combination, Consideration Transferred, Total | $ 209.0 |  |  |  |
Management Fees Revenue |  |  | 2.4 |  |
PNC Bank [Member] |  |  |  |  |
Significant Accounting Policies [Line Items] |  |  |  |  |
Proceeds from Lines of Credit | 80.0 |  | 105.0 |  |
Line of Credit Facility, Maximum Borrowing Capacity | 150.0 |  | 80.0 |  |
Debt Instrument, Face Amount |  |  | 65.0 |  |
Term Loan [Member] |  |  |  |  |
Significant Accounting Policies [Line Items] |  |  |  |  |
Debt Instrument, Face Amount | $ 105.0 |  |  |  |
Scenario, Plan [Member] |  |  |  |  |
Significant Accounting Policies [Line Items] |  |  |  |  |
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent |  | 21.00% |  |  |
Accounting Standards Update 2016-09 [Member] |  |  |  |  |
Significant Accounting Policies [Line Items] |  |  |  |  |
New Accounting Pronouncement or Change in Accounting Principle, Effect of Change on Net Income |  |  | $ 2.4 |  |
Sales Revenue, Net [Member] |  |  |  |  |
Significant Accounting Policies [Line Items] |  |  |  |  |
Aggregate percentage of revenue the from customers accounted for more than 10% |  |  | 33.00% | 30.00% | 33.00%
Customer |  |  |  |  |
Significant Accounting Policies [Line Items] |  |  |  |  |
Accounts receivable, net |  |  | $ 2.7 |  |

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