Condensed Consolidated Statements of Cash Flows (unaudited) (USD $)	3 Months Ended
Mar. 31, 2012	Mar. 31, 2011
Cash flows from operating activities:
Net income	$ 1,912,119	$ 324,412
Adjustments to reconcile net income to net cash (used in) provided by operating activities:
Depreciation and amortization	986,913	920,410
Stock-based compensation expense	320,510	300,275
Deferred income taxes	(82,206)	(111,293)
Provision for inventory	49,558	711,533
Tax benefit from exercise of stock options	(394,076)
Changes in operating assets and liabilities:
Accounts receivable	358,471	2,753,690
Inventories	(1,769,606)	(374,014)
Prepaid expenses, other current and long-term assets	(324,152)	(580,852)
Long-term deposits and other	8,499	8,499
Accounts payable	(476,940)	(1,021,405)
Accrued expenses	(1,341,407)	(966,151)
Deferred revenue	(716,667)	(668,190)
Income taxes payable	(215,156)	2,198
Other long-term liabilities	(5,509)	(13,165)
Net cash (used in) provided by operating activities	(1,689,649)	1,285,947
Cash flows from investing activities:
Purchase of property and equipment, net	(224,059)	(76,570)
Net cash used in investing activities	(224,059)	(76,570)
Cash flows from financing activities:
Principal payments on debt	(400,000)	(400,000)
Proceeds from exercise of stock options	114,656	28,945
Tax benefit from exercise of stock options	394,076
Net cash provided by (used in) financing activities	108,732	(371,055)
Exchange rate impact on cash	30,932	38,556
(Decrease) increase in cash and cash equivalents	(1,774,044)	876,878
Cash and cash equivalents at beginning of period	35,777,222	28,201,932
Cash and cash equivalents at end of period	$ 34,003,178	$ 29,078,810

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Includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the Entity may deposit additional funds at any time and also effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months. Compensating balance arrangements that do not legally restrict the withdrawal or usage of cash amounts may be reported as Cash and Cash Equivalents, while legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or company statements of intention with regard to particular deposits are not generally reported as cash and cash equivalents. Includes cash and cash equivalents associated with the entity's continuing operations. Excludes cash and cash equivalents associated with the disposal group (and discontinued operation).