Warrants (Detail) - Warrant activity is summarized as follows: (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Outstanding at December 31	923,090	929,914	942,870
Outstanding at December 31 (in Dollars per share)	$ 7.77	$ 15.13	$ 16.36
Outstanding at December 31	$2.09 - $48.90	$2.80 - $169.47	$2.80 - $169.47
Warrants exercisable at December 31, 2012	863,090
Warrants exercisable at December 31, 2012 (in Dollars per share)	$ 7.92
Warrants exercisable at December 31, 2012	$2.09 - $48.90
Warrants issued	50,000	61,076
Warrants issued (in Dollars per share)	$ 2.26	$ 4.50
Warrants issued	$2.09 - $3.80	$4.50
Warrants exercised		(49,779)
Warrants exercised (in Dollars per share)		$ 7.92
Warrants exercised		$7.92
Warrants expired / forfeited	(56,824)	(24,253)
Warrants expired / forfeited (in Dollars per share)	$ 123.37	$ 50.95
Warrants expired / forfeited	$75.00- $169.47	$50.63 - $60.00