Consolidated Balance Sheets (USD $)
In Thousands, unless otherwise specified
Mar. 31, 2012
Dec. 31, 2011
Dec. 31, 2010
ASSETS      
Cash and cash equivalents $ 5,832 $ 7,571 $ 7,796
Investments 7,245 5,745 3,100
Accounts receivable, net 4,644 5,576 5,150
Inventory, net 2,800 2,760 1,905
Prepaid expenses and other current assets 1,255 1,008 777
Total current assets 21,776 22,660 18,728
Long-term investments 1,000 1,000 1,500
Equipment, furniture and leasehold improvements, net 6,521 5,980 3,287
Intangible assets, net   35 39
Other assets   92 92
Other assets 127 127  
Deferred tax asset 8,165 8,165 9,056
Total assets 37,589 37,932 32,702
LIABILITIES AND SHAREHOLDERS' EQUITY      
Accounts payable 883 961 1,100
Accrued expenses 1,886 2,246  
Accrued compensation   1,283 1,975
Other accrued expenses   963 1,781
Advance payments   177 101
Deferred revenue   138 26
Warrant liability     7,694
Other current liabilities   299 170
Other current liabilities 383 614  
Total current liabilities 3,152 3,821 12,847
Warrant liability     5,158
Total liabilities   3,821 18,005
Commitments and contingencies (Note 11)        
Shareholders' equity:      
Preferred stock, $.001 par value: authorized 10,000,000 shares: Series B Convertible Preferred stock, (liquidation preference of $5,659,000) stated value $1,000 per share, $.001 par value        
Common stock, $.001 par value: authorized 200,000,000 shares 24 24 21
Additional paid in capital 221,616 220,838 206,298
Accumulated deficit (187,108) (186,656) (191,622)
Treasury stock (95) (95)  
Total shareholders' equity 34,437 34,111 14,697
Total liabilities and shareholders' equity $ 37,589 $ 37,932 $ 32,702