Commitments and Contingencies - Additional Information (Detail) MMBTU in Millions		1 Months Ended				3 Months Ended
	May 01, 2015 USD ($)	Mar. 31, 2016 USD ($)	Jan. 31, 2016 USD ($)	Sep. 30, 2015 USD ($)	Dec. 31, 2014 Violation	Mar. 31, 2017 USD ($) MMBTU Settlement $ / MMBTU	Dec. 31, 2012 USD ($)
Commitments And Contingencies [Line Items]
Natural gas purchase commitments | MMBTU						1.2
Month purchase commitment period ends natural gas						2017-06
Natural gas purchase commitments weighted average cost, per unit | $ / MMBTU						3.17
Natural gas purchase commitments weighted average cost, amount						$ 3,800,000
Natural gas purchase commitments weighted average market value per unit | $ / MMBTU						3.03
Natural gas purchase commitments weighted average market value, amount						$ 3,600,000
Accrued liabilities for environmental matters						175,000
Penalty related to discharge water permit							$ 100,000
Estimated litigation liability						$ 0
Percentage of payment of investigation costs agreed by Hallowell Facility						50.00%
Insurance coverage of general liability and auto liability risks						$ 100,000,000
Product liability deductible per claim						$ 250,000
Confidential settlement agreement with family groups | Settlement						3
Liability reserve						$ 0
Pre-litigation demand amount	$ 18,000,000
Cherokee Facility [Member]
Commitments And Contingencies [Line Items]
Payment of liabilities for environmental matters		$ 100,000
Number of alleged violations | Violation					11
Environmental loss contingencies civil penalty		$ 26,000
Global Industrial Inc [Member]
Commitments And Contingencies [Line Items]
Claimed amount payable by Global for certain work			$ 3,600,000	$ 18,000,000
Estimated amount paid to Global of disputed amount				6,000,000
Adjusted Estimated Claim Amount			5,000,000
Liability amount			$ 0
Global Industrial Inc [Member] | EL Dorado Ammonia L.L.C [Member]
Commitments And Contingencies [Line Items]
Estimated amount paid to Global of disputed amount				$ 3,500,000