Condensed Consolidated Balance Sheets (Unaudited) (USD $)	Mar. 31, 2012	Dec. 31, 2011
Assets
Cash and cash equivalents	$ 59,956,972	$ 63,077,178
Short-term investments	24,036,525	24,739,998
Total cash, cash equivalents and short-term investments	83,993,497	87,817,176
Accounts receivable, net	9,525,602	9,853,682
Inventories	22,822,387	21,175,754
Other current assets	1,729,448	999,919
Total current assets	118,070,934	119,846,531
Marketable securities and other investments	16,139,604	21,268,777
Property and equipment, net	36,386,996	36,713,578
Other assets	241,671	232,594
Total assets	170,839,205	178,061,480
Liabilities:
Accounts payable	3,086,455	3,476,030
Accrued liabilities	7,517,163	12,437,921
Deferred revenue	4,126,323	4,423,980
Total current liabilities	14,729,941	20,337,931
Accrued income taxes	3,128,100	3,082,356
Total liabilities	17,858,041	23,420,287
Commitments and contingencies (Note 11)
Stockholders' equity:
Preferred stock, $.01 par value- Authorized - 1,500,000 shares Issued - none	0	0
Common stock, $.01 par value- Authorized - 45,000,000 shares Issued and Outstanding - 19,589,744 and 19,533,244 and 19,573,244 and 19,573,244 shares, respectively	195,898	195,733
Additional paid-in capital	219,737,936	219,062,043
Accumulated other comprehensive loss	(308,144)	(263,849)
Treasury stock, at cost - 56,500 and 0 shares, respectively	0	0
Accumulated deficit	(66,644,526)	(64,352,734)
Total stockholders' equity	152,981,164	154,641,193
Total liabilities and stockholders' equity	$ 170,839,205	$ 178,061,480