Condensed Consolidated Statements of Cash Flows (unaudited) (USD $)	9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011
Cash flows from operating activities:
Net income	$ 7,294,237	$ 5,583,570
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	3,364,432	2,943,295
Stock-based compensation expense	914,003	901,619
Deferred income taxes	(1,012,571)	1,116,456
Provision for doubtful accounts	135,353
Provision for inventory	790,379	642,120
Tax benefit from exercise of stock options	(456,796)
Changes in operating assets and liabilities:
Accounts receivable	716,874	(2,721,155)
Inventories	(2,433,367)	516,647
Prepaid expenses, other current and long-term assets	429,718	454,804
Long-term deposits and other	25,496	162,997
Accounts payable	(2,399,999)	(6,252,826)
Accrued expenses	(873,153)	51,152
Deferred revenue	(2,150,000)	(1,884,307)
Income taxes payable	1,398,008	1,368,665
Other long-term liabilities	(6,318)	(17,224)
Net cash provided by operating activities	5,736,296	2,865,813
Cash flows from investing activities:
Purchase of property and equipment	(1,292,487)	(953,952)
Net cash used in investing activities	(1,292,487)	(953,952)
Cash flows from financing activities:
Principal payments on debt	(1,200,000)	(1,200,000)
Proceeds from exercise of stock options	331,639	151,770
Tax benefit from exercise of stock options	456,796
Net cash used in financing activities	(411,565)	(1,048,230)
Exchange rate impact on cash	46,390	(16,899)
Increase in cash and cash equivalents	4,078,634	846,732
Cash and cash equivalents at beginning of period	35,777,222	28,201,932
Cash and cash equivalents at end of period	$ 39,855,856	$ 29,048,664