Private Placements - Additional Information (Detail) (USD $)	1 Months Ended		6 Months Ended				1 Months Ended		1 Months Ended
	Feb. 29, 2012	May 31, 2011	Jun. 30, 2012	Jun. 30, 2011	Dec. 31, 2011	May 06, 2011	Feb. 29, 2012 Private Placement	Feb. 02, 2012 Private Placement	Jan. 18, 2012 Lansdowne Partners Limited Partnership, Greenway Capital Partners and Paragon Associates	Mar. 31, 2010 Lansdowne Partners Limited Partnership, Greenway Capital Partners and Paragon Associates	Feb. 02, 2012 Lansdowne Partners Limited Partnership, Greenway Capital Partners and Paragon Associates	Mar. 05, 2010 Lansdowne Partners Limited Partnership, Greenway Capital Partners and Paragon Associates
Subsidiary, Sale of Stock [Line Items]
Common stock shares issued		1,175,512					5,257,267			3,005,349
Common stock issued, price per share						$ 1.99		$ 1.50				$ 1.31
Net proceeds from issuance of common stock			$ 7,664,965	$ 2,179,535
Net proceeds from issuance of shares in Private Placement	7,822,000									3,879,403
Registration statement filing period after closing of Private Placement											90 days	45 days
Registration statement effective period after closing of Private Placement											180 days	120 days
Number of shares included in a registration statement to be registered with the SEC												3,005,349
Common stock classified outside of stockholders' equity (deficit)			$ 10,925,724		$ 7,854,682						$ 7,884,400	$ 3,879,403
Common stock purchased									3,658,676