Note 2 - Summary of significant accounting policies (Detail) (USD $)	3 Months Ended		3 Months Ended
	Mar. 31, 2013	Dec. 31, 2012	Mar. 31, 2013 Certificates of Deposit [Member] Beyond [Member]	Mar. 31, 2013 Certificates of Deposit [Member] Less Than [Member]	Mar. 31, 2013 Corporate Bond Securities [Member] Less Than [Member]	Mar. 31, 2013 Grant and Contract Revenue From USA [Member]	Mar. 31, 2012 Grant and Contract Revenue From USA [Member]	Mar. 31, 2013 Short-Term Investments Located Outside United States [Member]	Mar. 31, 2012 Short-Term Investments Located Outside United States [Member]	Mar. 31, 2013 Accounts Receivable [Member]	Mar. 31, 2013 Majority Owned Subsidiaries [Member]
Cash Equivalents, at Carrying Value (in Dollars)	$ 8,600,258	$ 13,009,688
Cash and Highly Liquid Investments Maturity	90 years
Subsidiary Cash Total (in Dollars)											6.4
Short-Term Investments Maturity			3 years	1 year	1 year
Concentration Risk, Percentage						31.50%	100.00%	68.50%	0.00%
Credit Term										30 days
Allowance for Doubtful Accounts Receivable (in Dollars)	$ 0	$ 0
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized (in Shares)	10,000,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant (in Shares)	2,900,000
Share-Based Compensation Arrangement By Share-Based Payment Award Number Of Shares Limited Per Year (in Shares)	400,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Outstanding, Weighted Average Remaining Contractual Terms	10 years