Subsequent Events - Additional Information (Detail) (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended	109 Months Ended	0 Months Ended
	Dec. 31, 2013	Jun. 30, 2014	Aug. 05, 2014 Subsequent Event
Subsequent Event [Line Items]
Common stock shares issued and sold	21,303,750		30,000,000
Additional purchase of common stock shares			15,000,000
Warrant agreement exercise price, fair value		$ 2.70	$ 0.85
Warrants expiration date	Dec. 16, 2018		Aug. 05, 2019
Proceeds from issuance of common stock and common stock units		$ 205,340	$ 18,000