Notes Payable - Additional Information (Detail) - HD Special-Situations III, L.P. - USD ($)					3 Months Ended		9 Months Ended
	Mar. 29, 2018	Nov. 13, 2017	Jun. 30, 2017	Mar. 23, 2017	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Senior Secured Term Note
Debt Instrument [Line Items]
Debt principal amount				$ 7,000,000
Debt principal repayment			$ 500,000
Debt instrument, initial repayment date				Jun. 30, 2017
Debt instrument, payment terms							$7.00 million principal amount Senior Secured Term Note (the “Note”) bearing interest at 11.5% per annum with principal of $0.50 million due and paid on June 30, 2017, and the remaining balance due 48 months after issuance for cash at par pursuant to a Note Purchase Agreement (the “Purchase Agreement”).
Interest rate				11.50%
Minimum principal reductions per month		$ 30,000
Minimum principal reductions, begining period		2018-04
Warrants issued to purchase of common stock		500,000
Warrant exercise price per share		$ 2.26
Warrants expiration period		2023-11
Fair value of warrants recognized as an increase in additional paid-in-capital							$ 370,000
Total interest expense recognized					$ 80,000	$ 220,000	$ 640,000	$ 540,000
Senior Secured Term Note | Purchase Agreement
Debt Instrument [Line Items]
Debt, remaining principal payable period							48 months
Senior Secured Term Note | Loan Agreement | M&I Brazil | Former Chairman of AETI
Debt Instrument [Line Items]
Interest rate	10.00%
Line of credit facility, agreement date	Mar. 29, 2018
Line of credit facility, maximum borrowing capacity	$ 300,000
Loan facility drawn and outstanding					$ 200,000		$ 200,000
Debt instrument, interest rate terms							the interest rate on the loan facility is 10.0%, per annum, payable each quarter.
Debt instrument, maturity date	Jun. 07, 2019
Revolving Credit Facility
Debt Instrument [Line Items]
Proceeds from sale of note available for working capital and general business purposes				$ 1,000,000