Income Taxes - Significant components of deferred tax assets and liabilities (Details 3) (USD $)	Dec. 31, 2012	Dec. 31, 2011
United States
Income Taxes [Line Items]
Intangible assets	$ 130,000	$ 200,000
Non-employee stock based compensation	(1,556,000)	(1,556,000)
Deferred revenue	2,779,000	2,106,000
Other reserves and accruals	1,621,000	1,121,000
Research and development tax credit carryforwards		74,000
Property, plant and equipment	1,541,000	1,127,000
Amortization of stock-based compensation	8,495,000	7,900,000
Capitalized research & development expenditures	15,846,000	15,162,000
Section 382 recognized built in loss	(15,202,000)	(1,819,000)
Net operating loss carryforwards	3,347,000	30,271,000
Total deferred tax asset	17,001,000	54,586,000
Valuation allowance	(17,001,000)	(54,586,000)
Net deferred tax assets
Foreign
Income Taxes [Line Items]
Intangible assets	694,000	325,000
Non-employee stock based compensation
Deferred revenue
Other reserves and accruals
Research and development tax credit carryforwards	1,569,000	1,533,000
Property, plant and equipment	541,000	529,000
Amortization of stock-based compensation
Capitalized research & development expenditures	5,384,000	4,760,000
Section 382 recognized built in loss
Net operating loss carryforwards	3,541,000	3,462,000
Total deferred tax asset	11,729,000	10,609,000
Valuation allowance	(11,729,000)	(10,609,000)
Net deferred tax assets