Accrued Liabilities (Details) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2014	Dec. 31, 2012	Dec. 31, 2011
Payables and Accruals [Abstract]
Payroll and related	$ 9,537,000	$ 9,068,000
Professional fees	1,400,000	1,441,000
Non-income taxes	3,223,000	1,544,000
Product warranty	578,000	616,000	1,006,000	1,126,000
Deferred rent	278,000	160,000
Derivative litigation settlement	1,241,000	0
Other	3,206,000	1,716,000
Total accrued liabilities	19,463,000	14,545,000
Derivative litigation costs in excess of insurance limits	$ 1,900,000