Commitments and Contingencies (Details) (USD $)	3 Months Ended
	Mar. 31, 2013 sqft	Mar. 31, 2012
Product Warranty [Abstract]
Period of warranty	12 months
Change in warranty accrual [Roll Forward]
Beginning accrued warranty and related costs	$ 588,000	$ 1,003,000
Accruals for warranties issued	264,000	102,000
Adjustments related to pre-existing warranties including expirations and changes in estimates	166,000	(8,000)
Cost of warranty repair	(269,000)	(100,000)
Ending accrued warranty and related costs	749,000	997,000
Contractual Obligations [Abstract]
Area of property under long-term operating lease (in square feet)	27,760
Period of operating lease	7 years
Period to be lapsed for cancelling lease	5 years
Term of royalty agreement	8 years
Aggregate amount payable towards royalty	7,000,000
Outstanding contractual obligations [Abstract]
Total	4,842,000
Less than 1 year	1,189,000
1-3 years	2,072,000
4-5 years	1,150,000
More than 5 years	431,000
Operating leases [Member]
Outstanding contractual obligations [Abstract]
Total	917,000
Less than 1 year	389,000
1-3 years	528,000
4-5 years	0
More than 5 years	0
Royalty agreement [Member]
Outstanding contractual obligations [Abstract]
Total	3,925,000
Less than 1 year	800,000
1-3 years	1,544,000
4-5 years	1,150,000
More than 5 years	$ 431,000