Summary of Significant Accounting Policies (Details) (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012	Dec. 31, 2012
Cash, Cash Equivalents and Marketable Securities
Impairment charge	$ 0	$ 0	$ 0	$ 0
Property and Equipment
Gross	1,360,000		1,360,000		1,318,000
Less accumulated depreciation	(1,210,000)		(1,210,000)		(1,043,000)
Net	150,000		150,000		275,000
Disposal of property and equipment			0	0
Comprehensive (Loss) Income
Reclassifications out of accumulated other comprehensive loss related to marketable securities	0	0	0	0
Minimum
Property and Equipment
Estimated useful lives			1 year
Maximum
Property and Equipment
Estimated useful lives			5 years
Cameras
Property and Equipment
Gross	923,000		923,000		923,000
Computer hardware and electronics
Property and Equipment
Gross	182,000		182,000		147,000
Furniture and fixtures
Property and Equipment
Gross	234,000		234,000		227,000
Software
Property and Equipment
Gross	$ 21,000		$ 21,000		$ 21,000