Loans Payable - Summary of Significant Conversion Option Valuation Inputs and Results (Detail) - After Modification [Member] - Binomial Lattice Process [Member] - Share Purchase Options Classified in Equity [Member]	12 Months Ended
	Dec. 31, 2017 $ / shares
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Underlying price on valuation date	$ 1.25
Contractual conversion rate	$ 1.00
Contractual term to maturity	1 year 9 months 26 days
Implied expected term to maturity	1 year 9 months 26 days
Market volatility:
Equivalent volatilities	120.10%
Equivalent market risk adjusted interest rates	0.52%
Minimum [Member]
Market volatility:
Range of volatilities	96.00%
Risk free rates using zero coupon US Treasury Security rates	0.29%
Maximum [Member]
Market volatility:
Range of volatilities	154.00%
Risk free rates using zero coupon US Treasury Security rates	0.68%