Warrants (Detail) (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2012
Proceeds from Warrant Exercises (in Dollars)	$ 394
Derivative, Number of Instruments Held		379,678
Common Stock [Member]
Stock Issued During Period, Shares, Warrants Exercised (in Shares)	49,779