Income Taxes - Additional Information (Detail) - USD ($)	6 Months Ended	12 Months Ended
	Jun. 30, 2018	Dec. 31, 2017	Jun. 30, 2017
Income Taxes Disclosure [Line Items]
US federal tax rate	21.00%	35.00%
Net operating losses carryback period	2 years
Capital losses carryback period	3 years
Net change in valuation allowance, for deferred tax asset	$ 3,400,000
Net operating loss carryforward	6,900,000
Loss carryforwards per year	2,800,000
Unrecognized tax benefits	0		$ 0
Brazil [Member]
Income Taxes Disclosure [Line Items]
Valuation allowance	6,600,000
Maybrooke [Member]
Income Taxes Disclosure [Line Items]
Valuation allowance	1,200,000
Malta [Member]
Income Taxes Disclosure [Line Items]
Valuation allowance	1,200,000
ARIS [Member]
Income Taxes Disclosure [Line Items]
Net operating loss carryforward	$ 600,000