Summary of Significant Accounting Policies - Additional Information (Detail) - USD ($) $ in Millions		3 Months Ended			12 Months Ended
	Oct. 10, 2017	Mar. 31, 2018	Dec. 31, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017
Significant Accounting Policies [Line Items]
Entity Incorporation Date Of Incorporation		Jan. 11, 1991
Concentration risk, customer		one customer accounting for 11% of the Companys revenues		two customers each accounted for 10% or more of the Companys revenues
Options and warrants excluded from the calculation of diluted shares		2,948,848		2,948,848
Production and importation permission description		22 million pounds in 2015 and was reduced by approximately 4.5 million pounds each year and ending at zero in 2020.
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent		35.00%
Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Amount			$ 1.4
Payables to Customers		$ 10.3	$ 9.8			$ 9.8
Business Combination, Consideration Transferred, Total	$ 209.0
Fees and Commissions		0.6		$ 0.6
Operating Loss Carryforwards		$ 5.4
Operating Loss Carryforwards, Limitations on Use		$4.1 million of which are subject to annual limitations of approximately $1.3 million.
Operating Loss Carry Forwards Expirations Date		2024
State and Local Jurisdiction [Member]
Significant Accounting Policies [Line Items]
Operating Loss Carryforwards		$ 2.6
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		52.0
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%				39.00%
Customer
Significant Accounting Policies [Line Items]
Accounts receivable, net		$ 4.0		$ 7.1