Balance Sheet (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010
Inventories:
Raw materials	$ 14,099	$ 10,378
Work-in-process	4,250	2,324
Finished goods	52,300	45,363
Total inventories, net	70,649	58,065
Property and equipment:
Furniture and fixtures	6,706	9,110
Machinery and equipment	97,916	90,649
Leasehold improvements	7,079	5,625
Property Plant And Equipment Gross, Total	111,701	105,384
Less: accumulated depreciation and amortization	(71,232)	(65,559)
Property and equipment, Total	40,469	39,825
Accrued liabilities:
Accrued compensation	10,915	9,848
Accrued warranty	5,558	4,811
Accrued incentive compensation	7,917	11,512
Other	22,506	25,112
Accrued liabilities, Total	$ 46,896	$ 51,283