Financings - Additional Information (Detail) (J.P. Morgan Securities Inc., USD $) In Millions, except Share data, unless otherwise specified	0 Months Ended
	Feb. 17, 2015	Feb. 03, 2015	Feb. 03, 2015
J.P. Morgan Securities Inc.
Class of Stock [Line Items]
Stock issued during period	1,500,000	10,000,000
Issuance & sale of common stock in public offering price per share		$ 8.75	$ 8.75
Option granted, exercisable period		30 days
Option to purchase common stock	1,500,000	1,500,000
Sale of stock price per share		$ 8.225	$ 8.225
Expected net proceeds from issuance of common stock	$ 94.3