Stockholders' Equity (Details) (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Business Acquisition, Equity Interests Issued or Issuable [Line Items]
Common stock, authorized shares (in shares)	500,000,000	500,000,000
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Share issued from public offering (in shares)	3,925,000
Net proceeds from the issuance of common stock	$ 25,658,000	$ 0	$ 0
Warrant [Abstract]
Exercise price of warrants (in dollars per share)	$ 2.94
Outstanding Warrants [Member]
Warrant [Abstract]
Exercise price of warrants (in dollars per share)	$ 2.94
Fair value of warrant	800,000
Common Stock [Member]
Business Acquisition, Equity Interests Issued or Issuable [Line Items]
Common stock, authorized shares (in shares)	500,000,000
Common stock, par value (in dollars per share)	$ 0.01
Share issued from public offering (in shares)	6,304,102
Price per share (in dollars per share)	$ 4.07
Net proceeds from the issuance of common stock	$ 25,700,000
Common Stock [Member] | Outstanding Warrants [Member]
Business Acquisition, Equity Interests Issued or Issuable [Line Items]
Number of shares reserved (in shares)	329,932
Common Stock [Member] | Stock Options [Member]
Business Acquisition, Equity Interests Issued or Issuable [Line Items]
Number of shares reserved (in shares)	1,817,839
Common Stock [Member] | Restricted Stock Units (RSUs) [Member]
Business Acquisition, Equity Interests Issued or Issuable [Line Items]
Number of shares reserved (in shares)	215,525