Accounting Policies - Additional Information (Detail) (USD $)	6 Months Ended							0 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Dec. 31, 2012	Jun. 30, 2013 Warrant	Jun. 30, 2012 Warrant	Jun. 30, 2013 Embedded Derivative Financial Instruments	Jun. 30, 2012 Embedded Derivative Financial Instruments	Jan. 17, 2012 MIT
Accounting Policies [Line Items]
Fair value of goodwill acquired in MIT acquisition								$ 346,000
Fair value of patents acquired in MIT acquisition								14,000
Finite-Lived Intangible Asset, Useful Life								6 years
Expected amortization expense of identified intangibles in 2013	2,333
Expected amortization expense of identified intangibles in 2014	2,333
Expected amortization expense of identified intangibles in 2015	2,333
Expected amortization expense of identified intangibles in 2016	2,333
Expected amortization expense of identified intangibles in 2017	2,333
Expected amortization expense of identified intangibles in 2018	2,333
Debt discount	899,000		1,798,000	0	279,000	0	321,000
Accretion of debt discount	$ 899,000	$ 737,000