Stockholders' Equity - Additional Information (Detail) (USD $)	0 Months Ended	12 Months Ended	0 Months Ended
	Nov. 01, 2014	Dec. 31, 2014	May 09, 2014	Dec. 31, 2013
Class of Stock [Line Items]
Preferred stock, shares authorized		10,000,000		10,000,000
Preferred stock, par value per share		$ 0.0001		$ 0.0001
Preferred stock, shares issued		0		0
Preferred stock, shares outstanding		0		0
Common stock, shares authorized		100,000,000		100,000,000
Common stock, par value per share		$ 0.0001		$ 0.0001
Reverse stock split ratio		3
CPHX acquisition		$ 296,000
Common stock subscribed and paid, shares		5,990,000
Common stock subscribed and paid		2,995,000
Warrants, issued and outstanding		0		0
Options, issued and outstanding		3,600,000		0
Options issued to purchase shares	4,800,000	4,800,000
Options exercise price per share	$ 3.78	$ 3.78
Stock options, vesting period	3 years
Stock-based compensation charge		579,565
Unamortized Stock based compensation charges		9,852,599
Unamortized Stock based compensation charges, end date of amortization period based on vesting period		2018-10
Research and Development Employees [Member]
Class of Stock [Line Items]
Stock-based compensation charge		265,634
General and Administrative Employees [Member]
Class of Stock [Line Items]
Stock-based compensation charge		313,931
Share-based Compensation Award, Tranche One [Member]
Class of Stock [Line Items]
Options vesting, percentage on each anniversary date	33.33%
Common Stock [Member] | CannaPharmaRX [Member]
Class of Stock [Line Items]
CPHX acquisition, shares			9,000,000
CPHX acquisition			$ 296,000
Maximum [Member]
Class of Stock [Line Items]
Preferred stock, shares authorized		10,000,000