Condensed Consolidated Statements of Cash Flows (USD $)	9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010
Cash flows from operating activities:
Net income	$ 5,583,570	$ 2,965,295
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	2,943,295	2,455,701
Stock-based compensation expense	901,619	864,742
Deferred income taxes	1,116,456	890,352
Provision for doubtful accounts		272,723
Provision for inventory	642,120	592,241
Changes in operating assets and liabilities:
Accounts receivable	(2,721,155)	(3,467,618)
Inventories	516,647	(1,499,923)
Prepaid expenses, other current and long-term assets	454,804	880,396
Long-term deposits and other	162,997	16,091
Accounts payable	(6,252,826)	3,050,687
Accrued expenses	51,152	(755,781)
Deferred revenue	(1,884,307)	(2,076,468)
Income taxes payable	1,368,665
Other long-term liabilities	(17,224)	(104,073)
Net cash provided by operating activities	2,865,813	4,084,365
Cash flows from investing activities:
Purchase of property and equipment, net	(953,952)	(1,817,716)
Reduction in purchase price of subsidiary		105,300
Net cash used in investing activities	(953,952)	(1,712,416)
Cash flows from financing activities:
Principal payments on debt	(1,200,000)	(1,200,000)
Proceeds from exercise of stock options	151,770	197,243
Net cash used in financing activities	(1,048,230)	(1,002,757)
Exchange rate impact on cash	(16,899)	(30,259)
Increase in cash and cash equivalents	846,732	1,338,934
Cash and cash equivalents at beginning of period	28,201,932	24,426,990
Cash and cash equivalents at end of period	$ 29,048,664	$ 25,765,924