Condensed Consolidated Balance Sheets (USD $)	Sep. 30, 2012	Dec. 31, 2011
Current Assets:
Cash and cash equivalents	$ 25,965,711	$ 21,300,733
Short-term investments	3,178,050	5,108,189
Accounts receivable, net of allowance of $325,000 and $450,000 at September 30, 2012 and December 31, 2011, respectively	14,551,275	11,780,135
Inventory, net	10,430,832	11,484,761
Prepaid expenses and other current assets	2,268,761	2,089,676
Deferred income tax assets, net	7,082,926	9,968,929
Total current assets	63,477,555	61,732,423
Property and equipment, net	22,650,797	26,845,220
Deferred income tax assets, net	12,716,169	12,716,169
Intangible assets, net	3,332,276	3,224,006
Other long-term assets	409,940	444,933
Total assets	102,586,737	104,962,751
Current Liabilities:
Accounts payable	4,259,347	4,513,938
Accrued liabilities	8,929,766	7,643,004
Current portion of deferred revenue	3,898,535	3,317,641
Customer deposits	327,640	413,314
Total current liabilities	17,415,288	15,887,897
Deferred revenue, net of current portion	6,649,519	4,636,901
Liability for unrecorded tax benefits	2,206,551	1,982,399
Total liabilities	26,271,358	22,507,197
Commitments and Contingencies
Stockholders' Equity
Preferred stock, $0.00001 par value per share; 25 million shares authorized; no shares issued and outstanding at September 30, 2012 and December 31, 2011
Common stock, $0.00001 par value per share; 200 million shares authorized; 52,331,998 and 55,696,608 shares issued and outstanding at September 30, 2012 and December 31, 2011, respectively	657	652
Additional paid-in capital	104,525,144	101,597,626
Treasury stock at cost,13,363,789 and 9,556,183 shares at September 30, 2012 and December 31, 2011, respectively	(67,203,043)	(47,207,093)
Retained earnings	39,068,261	28,145,325
Accumulated other comprehensive loss	(75,640)	(80,956)
Total stockholders' equity	76,315,379	82,455,554
Total liabilities and stockholders' equity	$ 102,586,737	$ 104,962,751