Consolidated Statements of Cash flows (Unaudited) (USD $)	9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010
Cash Flows from Operating Activities:
Net Loss	$ (1,138,815)	$ (4,187,472)
Adjustments to reconcile net loss to net cash (used) provided by operating activities:
Loss on impairment	1,353,857
Depreciation and amortization	6,112,612	5,243,225
Bond premium amortization	304,346
Loss on write down / disposal of property and equipment, net	826,170	83,179
Provision for doubtful accounts	22,047	2,764
Provision / write-off of excess and obsolete inventory	746,669	1,086,795
Provision for warranty	249,652	594,196
Stock-based compensation expense	2,533,444	2,838,998
Litigation judgment accrual	3,300,000
Excess tax benefits from stock-based compensation		(97,273)
Deferred income taxes	(2,479,787)	(1,327,426)
Provision for unrecognized tax benefits	357,506	(3,148)
Change in assets and liabilities:
Accounts receivable	991,401	2,425,430
Inventory	1,206,962	(4,026,860)
Prepaids and other assets	(309,166)	(1,617,257)
Accounts payable and accrued liabilities	1,009,573	(3,715,501)
Deferred revenue	(284,916)	411,830
Customer deposits	(164,171)	(124,623)
Net cash provided (used) by operating activities	14,637,384	(2,413,143)
Cash Flows from Investing Activities:
Purchases of investments	(11,479,493)
Proceeds from call / maturity of investments	5,000,000
Proceeds from disposal of capital assets	148,000	26,020
Purchases of property and equipment	(1,171,193)	(3,601,501)
Purchases of intangible assets	(310,501)	(275,988)
Net cash used by investing activities	(7,813,187)	(3,851,469)
Cash Flows from Financing Activities:
Excess tax benefits from stock-based compensation		97,273
Repurchase of common stock	(24,888,817)
Proceeds from stock options exercised	43,546	968,913
Net cash (used) provided by financing activities	(24,845,271)	1,066,186
Effect of exchange rate change on cash and cash equivalents	(88,309)	(25,549)
Net decrease in cash and cash equivalents	(18,021,074)	(5,198,426)
Cash and cash equivalents, beginning of period	42,684,241	45,505,049
Cash and cash equivalents, end of period	24,574,858	40,281,074
Supplemental Disclosure:
Cash paid for income taxes - net	49,659	703,982
Non-Cash Transactions:
Property and equipment purchases in accounts payable	$ 42,473	$ 76,909