Note 11 - Stockholders' Equity and Stock Plans (Details) - Options and Bonus Shares Available for Future Issuance	Mar. 31, 2014
1989 Non Qualified Option Plan [Member] | Authorized by Directors and Stockholders [Member]
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items]
Options and Bonus Shares available for future issuance	3,975,000
1989 Non Qualified Option Plan [Member] | Options Previously Exercised [Member]
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items]
Options and Bonus Shares available for future issuance	(3,214,687)
1989 Non Qualified Option Plan [Member] | Options Outstanding [Member]
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items]
Options and Bonus Shares available for future issuance	(436,000)
1989 Non Qualified Option Plan [Member] | Remaining For Future Issuance [Member]
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items]
Options and Bonus Shares available for future issuance	324,313
1994 Stock Incentive Plan [Member] | Authorized by Directors and Stockholders [Member]
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items]
Options and Bonus Shares available for future issuance	3,525,000
1994 Stock Incentive Plan [Member] | Options Previously Exercised [Member]
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items]
Options and Bonus Shares available for future issuance	(2,025,187)
1994 Stock Incentive Plan [Member] | Bonus Shares Previously Granted [Member]
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items]
Options and Bonus Shares available for future issuance	(93,750)
1994 Stock Incentive Plan [Member] | Options Outstanding [Member]
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items]
Options and Bonus Shares available for future issuance	(1,051,750)
1994 Stock Incentive Plan [Member] | Remaining For Future Issuance [Member]
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items]
Options and Bonus Shares available for future issuance	354,313
1996 Directors Stock Option Plan [Member] | Authorized by Directors and Stockholders [Member]
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items]
Options and Bonus Shares available for future issuance	750,000
1996 Directors Stock Option Plan [Member] | Options Previously Exercised [Member]
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items]
Options and Bonus Shares available for future issuance	(100,000)
1996 Directors Stock Option Plan [Member] | Options Outstanding [Member]
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items]
Options and Bonus Shares available for future issuance	(205,000)
1996 Directors Stock Option Plan [Member] | Remaining For Future Issuance [Member]
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items]
Options and Bonus Shares available for future issuance	445,000
Authorized by Directors and Stockholders [Member]
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items]
Options and Bonus Shares available for future issuance	8,250,000
Options Previously Exercised [Member]
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items]
Options and Bonus Shares available for future issuance	(5,339,874)
Bonus Shares Previously Granted [Member]
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items]
Options and Bonus Shares available for future issuance	(93,750)
Options Outstanding [Member]
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items]
Options and Bonus Shares available for future issuance	(1,692,750)
Remaining For Future Issuance [Member]
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items]
Options and Bonus Shares available for future issuance	1,123,626