Stockholders' Equity (Detail) (USD $) In Millions, except Share data, unless otherwise specified	0 Months Ended									0 Months Ended		12 Months Ended					0 Months Ended
	Jun. 30, 2011	Jun. 28, 2011	Dec. 31, 2012	Nov. 26, 2012	May 23, 2012	Dec. 31, 2011	Jun. 30, 2011 Underwriting Agreement [Member]	Jun. 28, 2011 Underwriting Agreement [Member]	Jun. 28, 2011 IPO [Member]	Jun. 28, 2011 Reporting Entity [Member]	Jun. 28, 2011 Selling Stockholders [Member]	Dec. 31, 2012 Purchase Agreementwith LPC [Member] Minimum [Member]	Dec. 31, 2012 Purchase Agreementwith LPC [Member] Maximum [Member]	Dec. 31, 2012 Purchase Agreementwith LPC [Member]	Oct. 13, 2011 Purchase Agreementwith LPC [Member]	Oct. 07, 2011 Purchase Agreementwith LPC [Member]	Jun. 30, 2011 Underwriters Over-Allotment Option [Member]	May 21, 2012 Shelf Registration [Member]
Common Stock, Shares Authorized			24,000,000		24,000,000	12,000,000
Common Stock And Preferred Stock Shares Authorized			24,100,000
Common Stock, Par or Stated Value Per Share (in Dollars per share)			$ 0.01			$ 0.01
Preferred Stock, Shares Authorized			100,000			100,000
Preferred Stock, Par or Stated Value Per Share (in Dollars per share)			$ 0.01			$ 0.01
Common Stock, Shares, Issued			7,254,464	23,149		7,218,807
Stock Purchase Agreement Authorized Amount (in Dollars)														$ 10.0		$ 10.0		$ 50.0
Stock Purchase Agreement Period In Force														30 months
Stock Purchase Agreement Number of Shares Registered															1,823,577
Stock Issued During Period Shares Issued As Commitment Fees														40,247
Stock Issued During Period Shares Issued As Additional Commitment Fees														80,494
Stock Purchase Agreement Remaining Number of Shares Authorized to be Sold														1,702,836
Sale of Stock Maximum Sale Per Transaction (in Dollars)												0.5	1.5
Stock Purchase Agreement Exchange Cap														1,434,994
Stock Purchase Agreement Exchange Rate Cap														19.99%
Debt Instrument, Convertible, Conversion Price (in Dollars per share)														$ 3.014
Stock Issued During Period, Shares, New Issues	3,053,750	2,725,000								2,645,000	80,000						408,750
Share Price (in Dollars per share)								$ 3.5208	$ 3.75					$ 2.17
Option to purchase Additional Shares, Period from Underwriting Agreement Date	30 days
Proceeds from Issuance Initial Public Offering (in Dollars)	$ 10.2
Class of Warrant or Right, Number of Securities Called by Warrants or Rights							61,076
Securities Called by Warrants, Expressed as a Percentage of Shares Issued in the Offering	2.00%
Class of Warrant or Right, Exercise Price of Warrants or Rights (in Dollars per Item)	4.50
Class of Warrant or Right, Exercise Price of Warrants or Rights, Expressed as Percentage of Public Offering Price	120.00%